Correct option is B
The correct answer is (b) Program Counter
The Program Counter (PC) is a register in a computer's CPU that stores the address of the next instruction to be executed. After the current instruction is executed, the Program Counter is updated to point to the next instruction.
Additional Information:
Program Counter (PC):
The Program Counter (PC) is a vital component of a computer's Central Processing Unit (CPU). It plays a key role in the instruction execution cycle by keeping track of where the next instruction is located in memory.
Functionality:
Types of Program Counter Usage:
- The Program Counter holds the memory address of the next instruction to be fetched from memory.
- After fetching the current instruction, the Program Counter is incremented (usually by 1) to point to the next instruction in sequence.
- For control flow instructions (like jumps, branches, or calls), the Program Counter is updated with the address specified in the instruction to enable non-sequential execution.
Incrementing PC:
- In most cases, the Program Counter automatically increments after each instruction to fetch the next sequential instruction.
Branch/Jump PC:
- When encountering a branch or jump instruction, the Program Counter is updated with a new address provided by the instruction.
- This allows the program to execute instructions in non-linear order, facilitating loops and conditional execution.
Key Role in CPU Operations:
- Enables sequential execution of instructions unless altered by control flow instructions.
- Ensures that the CPU always knows the location of the next instruction to execute.
The Program Counter is essential for the smooth and accurate functioning of any modern CPU.