The code used to boot up a computer is stored in A. RAM B. ROM C. PROM D. EPROM

Breakdown of the Problem

To determine where the code used to boot up a computer is stored, we need to analyze the options provided:

1. RAM (Random Access Memory): Volatile memory that loses data when power is turned off.
2. ROM (Read-Only Memory): Non-volatile memory that retains data even when the power is off and is used to store firmware.
3. PROM (Programmable Read-Only Memory): A type of ROM that can be programmed once after manufacturing.
4. EPROM (Erasable Programmable Read-Only Memory): A type of ROM that can be erased and reprogrammed using UV light.

Relevant Concepts

• The boot-up code, also known as firmware, is essential for initializing hardware and loading the operating system.
• ROM is designed specifically for storing firmware and essential boot code, which remains intact even when the power is OFF.

Analysis and Detail

• RAM is not suitable since it is erased upon shutdown.
• PROM is less common for boot code due to its one-time programmability.
• EPROM allows for erasing and reprogramming, but it is not the default medium for the initial boot code, which is fixed in most systems.

Given that the boot-up code must remain intact after power is lost, ROM is the preferred location for this critical software.

Verify and Summarize

Upon analyzing the properties of each type of memory, it is clear that the most apt choice for storing the boot-up code is ROM, as it retains the necessary instructions throughout power cycles.

Final Answer

The code used to boot up a computer is stored in B. ROM.