In an MCU the program is usually stored in the

In an MCU the program is usually stored in the

• A. RAM
• B. ROM
• C. EEPROM
• D. Flash

Answer: (B)

The key idea is that the program memory for a microcontroller must be non-volatile, so the code stays stored even when power is removed. The CPU fetches instructions from this memory as it runs. RAM holds data temporarily and loses its contents when power is off, so it isn’t used to store the program. EEPROM and Flash are also non-volatile and writable, but the traditional term used to denote the non-volatile storage that holds the firmware is ROM, which is why this option is considered the best match for where the program is stored in an MCU. (In many modern MCUs, that role is fulfilled by Flash, but it’s still non-volatile program storage.)

The key idea is that the program memory for a microcontroller must be non-volatile, so the code stays stored even when power is removed. The CPU fetches instructions from this memory as it runs. RAM holds data temporarily and loses its contents when power is off, so it isn’t used to store the program. EEPROM and Flash are also non-volatile and writable, but the traditional term used to denote the non-volatile storage that holds the firmware is ROM, which is why this option is considered the best match for where the program is stored in an MCU. (In many modern MCUs, that role is fulfilled by Flash, but it’s still non-volatile program storage.)