The correct answer is Cache Memory.

• ​Cache memory
  • It is a high-speed storage area for temporary storage.
  • It is the smaller and fastest memory component in the computer.
  • It is used during the reading and writing processes from the disk.
  • It acts as a buffer between RAM and the CPU.
• CD ROM
  • It is a pre-pressed optical compact disc that contains data.
  • It is read-only.
  • Computers can read but not write or erase data on CD-ROMs.
• Hard Disk
  • It is rigid magnetic disc that stores data.
  • It is located within a drive unit.
  • It is a non-volatile storage device that contains platters and magnetic disks rotating at high speeds.
• Auxiliary Memory
  • It is known as the lowest-cost, highest-capacity and slowest-access storage in a computer system.
  • It is where programs and data are kept for long-term storage or when not in immediate use.
  • The most common examples of auxiliary memories are magnetic tapes and magnetic disks.

• ROM: Read-Only Memory
  • It refers to computer memory chips containing permanent or semi-permanent data.
  • It is non-volatile.
  • The data remains intact even when the power is switched off.
  • It contains the programming needed to start a PC, which is essential for boot-up.
  • It performs major input/output tasks and holds programs or software instructions.
  • It is the permanent memory built into your computer.
• RAM: Random Access Memory
  • It is a hardware device that allows information to be stored and retrieved on a computer.
  • It is volatile.
  • The data is erased even when the power is switched off.
  • The programs and data that the CPU requires during the execution of a program are stored in this memory.