Which component is often found on the motherboard?

The correct answer is the CPU, which is an essential component located directly on the motherboard. The CPU, or Central Processing Unit, is often referred to as the brain of the computer, as it performs most of the processing inside the system. It executes instructions from programs and manages tasks, making it crucial for the overall functionality of the computer.

In contrast, external drives, input devices (like keyboards and mice), and output devices (such as printers and monitors) are typically not located on the motherboard itself. External drives connect via ports, input devices interface through various connectors, and output devices carry out their functions separately and rely on the motherboard for processing but do not reside on it. Therefore, the CPU is the only component among the options provided that is integral to the motherboard's architecture and function.