11. A relationship between processes such that each has some part (critical section) which must not be executed while the critical section of another is being executed, is known as

A. semaphore
B. mutual exclusion
C. multiprogramming
D. multitasking
E. None of the above

12. What is the name of the operating system which was originally designed by scientists and engineers for use by
scientists and engineers?

A. XENIX
B. UNIX
C. OS/2
D. MS DOS
E. None of the above

13. The most common security failure is

A. carelessness by users
B. depending on passwords
C. too much emphasis on preventing physical access
D. insufficient technology used to prevent breaches
E. None of the above

14. Terminal Table

A. contains all constants in the program
B. a permanent table of decision rules in the form of patterns for matching with the uniform symbol table to discover syntactic structure.
C. consists of a full or partial list of the token’s as they appear in the program. Created by Lexical analysis and used for syntax analysis and interpretation
D. a permanent table which lists all keywords and special symbols of the language in symbolic form.
E. None of the above

15. Block or buffer caches are used

A. to improve disk performance
B. to handle interrupts
C. to increase the capacity of main memory
D. to speed up main memory read operation
E. None of the above