Which of the following does CPU memory include?

Concept

A CPU uses a hierarchy of small, high-speed storage close to its execution units. Registers or scratch-pad storage hold current operands and intermediate state, while cache keeps recently used instruction and data blocks to reduce access latency.

Secondary memory, such as an HDD or SSD, is persistent system storage reached through the storage and I/O path; it is not the processor’s immediate internal working store.

Application

The stem asks which listed memory forms belong to the CPU’s high-speed internal working hierarchy.

• Scratch-pad or register storage supplies the execution units with operands and holds intermediate results.

• Cache memory supplies recently used instruction and data blocks faster than main or secondary storage.

Contrast

• Secondary Memory describes persistent external storage rather than processor-local working storage.

• Only Scratch Pad Memory names the operand and intermediate-state layer but leaves out the cache layer.

• Only Cache Memory names the reuse-latency layer but leaves out scratch-pad or register storage.

Therefore, the complete listed choice is “Scratch Pad Memory and Cache Memory.”