Operating System MCQ (Multiple Choice Questions) - SchoolingAxis

Operating System MCQ (Multiple Choice Questions)

 Que- A large number of disks in a system improves the rate at which data can be read or written : 

a. if the disks are operated on sequentially 

b. if the disks are operated on selectively 

c. if the disks are operated in parallel 

d. all of the mentioned 


Answer- if the disks are operated in parallel        


Que- RAID stands for : 

a. Redundant Allocation of Inexpensive Disks 

b. Redundant Array of Important Disks 

c. Redundant Allocation of Independent Disks 

d. Redundant Array of Independent Disks 


Answer- Redundant Array of Independent Disks        


Que- If the mean time to failure of a single disk is 100,000 hours, then the mean time to failure of some disk in an array of 100 disks will be : 

a. 100 hours 

b. 10 days 

c. 10 hours 

d. 1000 hours 


Answer- 1000 hours        


Que- The solution to the problem of reliability is the introduction of __________ 

a. aging 

b. scheduling 

c. redundancy 

d. disks 


Answer- redundancy        


Que- The technique of duplicating every disk is known as : 

a. mirroring 

b. shadowing 

c. redundancy 

d. all of the mentioned 


Answer- mirroring        


Que- The mean time to failure of a mirrored disk depends on :I) the mean time to failure of individual disksII) the mean time to repair 

a. Only I 

b. Only II 

c. Both I and II 

d. Neither I nor II 


Answer- Both I and II        


Que- RAID level ________ refers to disk arrays with striping at the level of blocks, but without any redundancy. 

a. 0 

b. 1 

c. 2 

d. 3 


Answer- 0        


Que- RAID level _______ refers to disk mirroring. 

a. 0 

b. 1 

c. 2 

d. 3 


Answer- 1        


Que- RAID level ______ is also known as bit interleaved parity organisation. 

a. 0 

b. 1 

c. 2 

d. 3 


Answer- 3        


Que- A single parity bit can be used for : 

a. detection 

b. multiple error corrections 

c. few error corrections 

d. all of the mentioned 


Answer- detection        


Que- RAID  level ______ is also known as memory style error correcting code(ECC) organization. 

a. 1 

b. 2 

c. 3 

d. 4 


Answer- 2        


Que- RAID level 3 does not have _________ as in RAID level 1. 

a. efficiency 

b. enough storage space for data 

c. storage overhead 

d. time consumption overhead 


Answer- storage overhead        


Que- Tertiary storage is built with : 

a. a lot of money 

b. unremovable media 

c. removable media 

d. secondary storage 


Answer- removable media        


Que- Floppy disks are examples of : 

a. primary storage 

b. secondary storage 

c. tertiary storage 

d. none of the mentioned 


Answer- tertiary storage        


Que- A magneto-optic disk is : 

a. primary storage 

b. secondary storage 

c. removable disk 

d. none of the mentioned 


Answer- removable disk        


Que- The magneto-optic head flies ___________ the disk surface than a magnetic disk head does. 

a. much farther from 

b. much closer to 

c. at the same distance as 

d. none of the mentioned 


Answer- much farther from        


Que- Optical disks ______ magnetism. 

a. use 

b. do not use 

c. may use 

d. none of the mentioned 


Answer- do not use        


Que- The phase change disk is coated with a material that can freeze into either _______ or ________ state. 

a. crystalline, solid 

b. ice, amorphous 

c. crystalline, liquid 

d. crystalline, amorphous 


Answer- crystalline, amorphous        


Que- WORM stands for : 

a. write only, read mandatory 

b. write once, read many times 

c. write only once, read multiple 

d. none of the mentioned 


Answer- write once, read many times        


Que- A tape holds _______ data than optical or magnetic disk cartridge. 

a. lesser 

b. more 

c. much lesser 

d. none of the mentioned 


Answer- more        


Que- Random access to tape is _______ a disk seek. 

a. much slower than 

b. much faster than 

c. comparable to 

d. none of the mentioned 


Answer- much slower than        


Que- A typical tape drive is ________ a typical disk drive. 

a. more expensive than 

b. cheaper than 

c. of the same cost as 

d. none of the mentioned 


Answer- more expensive than        


Que- The surface area of a tape is ________ the surface area of a disk. 

a. much lesser than 

b. much larger than 

c. equal to 

d. none of the mentioned 


Answer- much larger than        


Que- In domain structure what is Access-right equal to ? 

a. Access-right = object-name, rights-set 

b. Access-right = read-name, write-set 

c. Access-right = read-name, execute-set 

d. Access-right = object-name, execute-set 


Answer- Access-right = object-name, rights-set        


Que- What is meaning of right-set ? 

a. It is a subset consist of read and write 

b. It is a subset of all valid operations that can be performed on the object 

c. It is a subset consist of read,write and execute 

d. None of the mentioned 


Answer- It is a subset of all valid operations that can be performed on the object        


Que- What is Domain ? 

a. Domain = Set of all objects 

b. It is a collection of protection policies 

c. Domain= set of access-rights 

d. None of the mentioned 


Answer- Domain= set of access-rights        


Que- What does access matrix represent ? 

a. Rows-Domains, Columns-Objects 

b. Rows-Objects, Columns-Domains 

c. Rows-Access List, Columns-Domains 

d. Rows-Domains, Columns-Access list 


Answer- Rows-Domains, Columns-Objects        


Que- What are the three additional operations to change the contents of the access-matrix ? 

a. copy 

b. Owner 

c. control 

d. all of the mentioned 


Answer- all of the mentioned        


Que- Who can add new rights and remove some rights ? 

a. copy 

b. transfer 

c. limited copy 

d. owner 


Answer- owner        


Que- What are the three copyrights ? 

a. copy 

b. transfer 

c. limited copy 

d. all of the mentioned 


Answer- all of the mentioned        


Que- Which two rights allow a process to change the entries in a column ? 

a. copy and transfer 

b. copy and owner 

c. owner and transfer 

d. deny and copy 


Answer- copy and transfer        


Que- Which is an unsolvable problem in access-matrix ? 

a. Owner override 

b. Brute force 

c. Access denied 

d. Confinement 


Answer- Confinement        


Que- Which of the following objects require protection ? 

a. CPU 

b. Printers 

c. Motherboard 

d. All of the mentioned 


Answer- Printers        


Que- What is 'separation' in security of Operating systems ? 

a. To have separate login for different users 

b. To have separate Hard disk drive/partition for different users 

c. It means keeping one user's objects separate from other users 

d. None of the mentioned 


Answer- It means keeping one user's objects separate from other users        


Que- Which of the following statements are correct? (i) Physical separation - in which process use different physical objects like separate printers (ii) Physical separation - in which process having different security requirement at different times (iii) Logical separation - In which users operate under illusion that no other processes exist (iv) Logical separation - In which processes conceal their data and computations 

a. i 

b. i and iii 

c. ii and iii 

d. iii and iv 


Answer- i and iii        


Que- Which of the following statements are correct? (i) Physical separation - in which process use different physical objects like separate printers (ii) Temporal separation - in which process having different security requirement at different times (iii) Physical separation - In which users operate under illusion that no other processes exist (iv) Temporal separation - In which processes conceal their data and computations 

a. i 

b. i and ii 

c. ii and iii 

d. iii and iv 


Answer- i and ii        


Que- Which of the following statements are correct? (i) logical separation - in which process use different physical objects like separate printers (ii) cryptographic separation - in which process having different security requirement at different times (iii) Logical separation - In which users operate under illusion that no other processes exist (iv) cryptographic separation - In which processes conceal their data and computations 

a. i 

b. i and ii 

c. ii and iii 

d. iii and iv 


Answer- iii and iv        


Que- What are various roles of protection ? 

a. It is used to detect errors which can prevent contamination of system 

b. It is used used to accelerate a process 

c. It is used to optimize system downtime 

d. None of the mentioned 


Answer- It is used to detect errors which can prevent contamination of system        


Que- Which of the following objects require protection ? 

a. Memory 

b. Monitor 

c. Power supply unit 

d. All of the mentioned 


Answer- Memory        


Que- Which principle states that programs, users and even the systems be given just enough privileges to perform their task? 

a. principle of operating system 

b. principle of least privilege 

c. principle of process scheduling 

d. none of the mentioned  


Answer- principle of least privilege        


Que- _______ is an approach to restricting system access to authorized users. 

a. Role-based access control 

b. Process-based access control 

c. Job-based access control 

d. None of the mentioned  


Answer- Role-based access control        


Que- For system protection, a process should access 

a. all the resources 

b. only those resources for which it has authorization 

c. few resources but authorization is not required 

d. all of the mentioned  


Answer- only those resources for which it has authorization        


Que- The protection domain of a process contains 

a. object name 

b. rights-set 

c. both object name and rights-set 

d. none of the mentioned  


Answer- both object name and rights-set        


Que- If the set of resources available to the process is fixed throughout the process's lifetime then its domain is 

a. static 

b. dynamic 

c. neither static nor dynamic 

d. none of the mentioned  


Answer- static        


Que- Access matrix model for user authentication contains 

a. a list of objects 

b. a list of domains 

c. a function which returns an object's type 

d. all of the mentioned  


Answer- all of the mentioned         


Que- Global table implementation of matrix table contains 

a. domain 

b. object 

c. right-set 

d. all of the mentioned  


Answer- all of the mentioned         


Que- For a domain _______ is a list of objects together with the operation allowed on these objects. 

a. capability list 

b. access list 

c. both capability and access list 

d. none of the mentioned  


Answer- capability list        


Que- Which one of the following is capability based protection system? 

a. hydra 

b. cambridge CAP system 

c. both hydra and cambridge CAP system 

d. none of the mentioned  


Answer- both hydra and cambridge CAP system        


Que- In UNIX, domain switch is accomplished via 

a. file system 

b. user 

c. superuser 

d. none of the mentioned  


Answer- file system        


Que- When an attempt is to make a machine or network resource unavailable to its intended users, the attack is called 

a. denial-of-service attack 

b. slow read attack 

c. spoofed attack 

d. starvation attack  


Answer- denial-of-service attack        


Que- The code segment that misuses its environment is called a 

a. internal thief 

b. trojan horse 

c. code stacker 

d. none of the mentioned  


Answer- trojan horse        


Que- The internal code of any software that will set of a malicious function when specified conditions are met, is called 

a. logic bomb 

b. trap door 

c. code stacker 

d. none of the mentioned  


Answer- logic bomb        


Que- The pattern that can be used to identify a virus is known as 

a. stealth 

b. virus signature 

c. armoured 

d. multipartite  


Answer- virus signature        


Que- Which one of the following is a process that uses the spawn mechanism to revage the system performance? 

a. worm 

b. trojan 

c. threat 

d. virus  


Answer- worm        


Que- What is a trap door in a program? 

a. a security hole, inserted at programming time in the system for later use 

b. a type of antivirus 

c. security hole in a network 

d. none of the mentioned  


Answer- a security hole, inserted at programming time in the system for later use        


Que- Which one of the following is not an attack, but a search for vulnerabilities to attack? 

a. denial of service 

b. port scanning 

c. memory access violation 

d. dumpster diving  


Answer- port scanning        


Que- File virus attaches itself to the 

a. source file 

b. object file 

c. executable file 

d. all of the mentioned  


Answer- executable file        


Que- Multipartite viruses attack on 

a. files 

b. boot sector 

c. memory 

d. all of the mentioned  


Answer- all of the mentioned         


Que- In asymmetric encryption 

a. same key is used for encryption and decryption 

b. different keys are used encryption and decryption 

c. no key is required for encryption and decryption 

d. none of the mentioned  


Answer- different keys are used encryption and decryption        


Que- What is true regarding 'Fence' ? 

a. Its a method to confine users to one side of a boundary 

b. It can protect Operating system from one user 

c. It cannot protect users from each other 

d. All of the mentioned 


Answer- All of the mentioned        


Que- What is not true regarding 'Fence' ? 

a. It is implemented via hardware register 

b. It doesn't protect users from each other 

c. It good to protect OS from abusive users 

d. Its implementation is unrestricted and can take any amount of space in Operating system. 


Answer- Its implementation is unrestricted and can take any amount of space in Operating system.        


Que- What is correct regarding 'relocation' w.r.t protecting memory ? 

a. It is a process of taking a program as if it began at address 0 

b. It is a process of taking a program as if it began at address 0A 

c. Fence cannot be used within relocation process 

d. All of the mentioned 


Answer- It is a process of taking a program as if it began at address 0        


Que- How can fence and relocation be used together ? 

a. To each program address, the contents of fence register are added 

b. To contents of fence register is subtracted from actual address of program 

c. To each program address, the contents of fence register are not added 

d. None of the mentioned 


Answer- To each program address, the contents of fence register are added        


Que- What is basic need in protecting memory in multi-user environment ? 

a. We need two registers one 'start' and other 'end' 

b. We need a variable register 

c. A fence register has to be used known as base register. 

d. None of the mentioned 


Answer- A fence register has to be used known as base register.        


Que- What is role of base/bound registers ? 

a. They give starting address to a program 

b. Program's addresses are neatly confined to space between the base and the bound registers 

c. They provide encrypted environment 

d. This technique doesn't protects a program's address from modification by another user 


Answer- Program's addresses are neatly confined to space between the base and the bound registers        


Previous Post Next Post