Which level of memory hierarchy has the fastest access time but smallest…

The memory hierarchy is organized based on a trade-off between speed and capacity. Cache memory sits closest to the CPU, designed specifically to store frequently accessed data for rapid retrieval. This proximity and specialized design grant it the fastest access time among all memory levels, often measured in nanoseconds. However, to maintain this speed and keep costs manageable, cache capacity is kept very small compared to other memory types. Main memory (RAM) offers larger storage but slower access, while secondary storage like hard drives provides vast capacity with significantly higher latency. Therefore, cache is the only option that satisfies both conditions of being fastest and smallest in capacity.