The correct answer is (A), (D), (B), (C)In computer architecture, memory hierarchy separates computer storage into a hierarchy based on response time. The memory hierarchy is an enhancement to organize the memory such that it can minimize the access time. Acess time refers to the time interval between the read/write request and the availability of data. Memory Hierarchy Design:As we move from the top level to the bottom level in the hierarchy, the access time increases. That is CPU Registers require the least amount of memory access time. Cache Memory requires more amount of memory access time as compared to CPU Registers. Main Memory requires more amount of memory access time as compared to Cache Memory. Secondary Memory requires more amount of memory access time as compared to Main Memory. The amount of access time required can be stated as: CPU Register