What is the primary component of a computer that processes instructions?

The central processing unit (CPU) is the primary component of a computer responsible for processing instructions. It performs the basic arithmetic, logic, control, and input/output (I/O) operations specified by the instructions. Essentially, the CPU is often referred to as the "brain" of the computer, as it executes computations and processes data to carry out tasks.

The CPU interprets and executes commands from the operating system and application programs, managing the workflow of tasks within the system. It interacts with other components, such as RAM, to fetch and store data, and communicates with the hardware via the motherboard.

In contrast, the hard drive serves as long-term storage, retaining data even when the computer is off, while RAM provides temporary storage for data being actively used or processed. The motherboard is the main circuit board that connects all components of the computer, but it does not process instructions on its own. Therefore, the CPU distinctly holds the key role of processing instructions, making it the correct answer.