Ace the A Level Computer Science OCR 2025 – Code Your Way to Success!

In a RISC (Reduced Instruction Set Computer) architecture, one of the defining characteristics of its registers is that they are of the same size and interchangeable. This uniformity allows for simplified instruction formats and reduces complexity in the design of the CPU. By having registers that are consistent in size, it becomes easier for the processor to manage data movement and to perform arithmetic or logical operations without needing to account for different register sizes.

This consistency also supports the efficient execution of pipelining, a technique that allows multiple instruction phases to be executed simultaneously, enhancing the overall performance of the processor. Interchangeability means that any register can be used for any purpose within the constraints of the instruction set, allowing for greater flexibility in programming and optimizing performance.

In contrast, varying sizes of registers for optimization would complicate instruction decoding and execution, which goes against the primary principles of RISC that focus on simplicity and speed. Moreover, registers in RISC architectures mainly facilitate simple instruction execution rather than complex ones, which is contrary to that option. Lastly, the implication that registers are limited strictly to single data operations doesn't capture the broader capabilities aligned with RISC, as they can be employed in various operations, not just singular data movements.