What is the main role of the CPU in a computer system?

The central processing unit (CPU) is often referred to as the brain of the computer. Its main role is to execute instructions and perform calculations, which involves processing data. The CPU takes input from various sources, such as memory and input devices, and follows a set of instructions to manipulate the data. This can include arithmetic operations, logic operations, and data movement.

Understanding this role helps clarify why the other options do not fit as the primary function of the CPU. The second option relates to storage, which is a job for memory components like RAM or hard drives. The third option, regarding providing power, pertains to the power supply unit of the computer, not the CPU. Finally, the generation of visual output is handled by the graphics processing unit (GPU) or the display adapter, rather than the CPU itself. Therefore, the correct answer highlights the CPU's critical function of carrying out computations and executing instructions, which is fundamental to a computer’s operation.