Free Test Scope and lifetime of ... – C Language

Q1: What is the main purpose of declaring a variable as register in C?

A. To store variable in CPU register for faster access B. To store variable in RAM permanently C. To make variable global D. To store variable in cache memory permanently

Q2: Where are register variables generally stored?

A. CPU registers B. Hard disk C. RAM stack section D. Heap memory

Q3: What is the default initial value of a register variable in C?

A. Garbage value B. Zero C. One D. NULL

Q4: Which of the following is NOT true about register variables?

A. They can be accessed faster than normal variables B. They can be declared globally C. They have block scope D. They have automatic storage duration

Q5: What will happen if CPU registers are not available for a register variable?

A. Compiler will store it in main memory B. Compiler will throw error C. Program will crash D. It will be stored in heap

Q6: Can you get the address of a register variable using & operator?

A. No B. Yes C. Only in global scope D. Only if explicitly casted

Q7: What is the scope of a register variable declared inside a function?

A. Local to the block in which it is declared B. Global to the program C. Local to the file D. Accessible in all functions

Q8: What is the lifetime of a register variable?

A. Till the control remains in the block B. Whole program execution C. Till the system shuts down D. Permanent

Q9: Which keyword is used to declare a register variable?

A. register B. auto C. static D. extern

Q10: What is the maximum number of register variables allowed?

A. Depends on CPU architecture B. Unlimited C. One per program D. 256 per program

Q11: Why can’t we apply sizeof operator to register variables?

A. Because their memory address is unknown B. Because they are constant C. Because they are stored in heap D. Because compiler does not allow keywords

Q12: Can register variables be used for storing large arrays?

A. No B. Yes C. Only globally D. Only if memory is free

Q13: Which type of variables are best suited for register storage?

A. Frequently accessed variables like loop counters B. Large arrays C. File handles D. Function pointers

Q14: If we declare register int x;, what will compiler do if no register is available?

A. Allocate in memory as auto variable B. Throw compilation error C. Use static memory D. Ignore variable

Q15: Can register variables be declared as static?

A. No B. Yes C. Only in global scope D. Only in main()

Q16: Are register variables stored in stack or heap if not in registers?

A. Stack B. Heap C. Data segment D. ROM

Q17: Which statement is correct for register variables?

A. They are faster to access B. They are slower than auto variables C. They are global by default D. They are initialized to zero

Q18: Can register be used for pointer variables?

A. Yes B. No C. Only for global variables D. Only for constants

Q19: Which of the following is a disadvantage of register variables?

A. Cannot take their address B. Slow access C. Occupy heap space D. Increase program size

Q20: What happens if we try to print address of a register variable?

A. Compilation error B. Runtime error C. Prints garbage D. Prints zero

Quiz for Scope and lifetime of variables register