Explanation:

Answer : b . ROM

BIOS (basic input/output system) is the program a computer's microprocessor uses to start the computer system after it is powered on. It also manages data flow between the computer's operating system (OS) and attached devices, such as the hard disk, video adapter, keyboard, mouse and printer.It is located in the ROM (Read-Only Memory) of the computer. More specifically, it resides in an erasable programmable read-only memory (EPROM) chip. So, as soon as you turn your computer on, the CPU accesses the EPROM and gives control to the BIOS. The BIOS also is used after the computer has booted u