ANS:A - RAM

Computer memory types

Volatile:

DRAM (e.g., DDR SDRAM)
SRAM
In development T-RAM
Z-RAM
TTRAM

Historical Delay line memory:
Selectron tube
Williams tube

Non-volatile:

ROM PROM
EPROM
EEPROM

Flash memory:
Early stage FeRAM
MRAM
PRAM

In development CBRAM:
SONOS
RRAM
Racetrack memory
NRAM
Millipede

Historical Drum memory:
Magnetic core memory
Plated wire memory
Bubble memory
Twistor memory

Semiconductor memory is an electronic data storage device, often used as computer memory.