Arrange the following in terms of their capacity from smallest to largest:
A. L3 Cache
B. L1 Cache
C. CPU Register
D. L2 Cache
Choose the correct answer from the options given below:

Correct option is C

To arrange these by capacity from smallest to largest, use the standard memory hierarchy. Here:
· A. L3 Cache
· B. L1 Cache
· C. CPU Register
· D. L2 Cache
Step-by-Step Solution
C. CPU Register: CPU registers are located directly within the processor and hold operands, addresses, instructions, and intermediate results. Their individual capacity is extremely small—typically only a few bytes.
Therefore, they have the smallest capacity among the given options.
B. L1 Cache: L1 (Level 1) cache is the smallest cache level and is designed for very fast access. It is typically divided into instruction and data caches. Its capacity is larger than registers but smaller than L2 and L3.
D. L2 Cache: L2 cache provides more storage than L1 cache, while being somewhat slower. It acts as an additional high-speed memory layer between L1 and L3.
A. L3 Cache: L3 cache is generally the largest of the three cache levels. In modern multicore processors, it is commonly shared among multiple CPU cores.
Final Order
Therefore, from smallest to largest capacity:
​$$\boxed{C \rightarrow B \rightarrow D \rightarrow A}$$​​
Information Booster
1. CPU Registers → Smallest capacity and fastest access.
2. L1 Cache → Smallest and fastest cache.
3. L2 Cache → Larger than L1 and generally slower.
4. L3 Cache → Generally the largest cache and often shared among CPU cores.
5. As we move farther from the CPU core, capacity generally increases while access speed decreases.
Additional Knowledge
Moving down this hierarchy generally means:
· Capacity increases
· Cost per bit decreases
· Access speed decreases