The correct answer is BIOS.
BIOS (Basic Input/Output System) is a type of firmware that is stored on a non-volatile memory chip on the motherboard and is responsible for initializing hardware during the booting process and providing runtime services for operating systems and programs.
- SSD (Solid State Drive) is a type of storage device, not firmware.
- CMOS (Complementary Metal-Oxide-Semiconductor) refers to the technology used to produce integrated circuits and typically relates to the chip that stores BIOS settings, but by itself, it's not considered firmware.
- RAM (Random Access Memory) is volatile memory used by the computer for temporary data storage while it is running and is not firmware.
Thus, BIOS is the correct choice when referring to firmware.