Answer : B
Definition :
Cache memory is a small-sized type of volatile computer memory that provides high-speed data access to a processor and stores frequently used computer programs, applications and data. It stores and retains data only until a computer is powered up.
Cache memory is the fastest memory in a computer. It is typically integrated on the motherboard and directly embedded on the processor or main random access memory (RAM).
Cache memory provides faster data storage and access by storing an instance of programs and data routinely accessed by the processor. Thus, when a processor requests data that already has an instance in the cache memory, it does not need to go to the main memory or the hard disk to fetch the data.
Cache memory can be primary or secondary cache memory, where primary cache memory is directly integrated or closest to the processor. In addition to hardware-based cache, cache memory also can be a disk cache, where a reserved portion on a disk stores and provide access to frequently accessed data/applications from the disk.