Which of the following components is most directly responsible for processing data in a computer?

The Central Processing Unit (CPU) is most directly responsible for processing data in a computer. The CPU acts as the brain of the computer, executing instructions from programs through processes like arithmetic, logic, and control operations. It retrieves data from memory, processes it according to the defined instructions, and sends the results back to memory or to output devices.

While the motherboard is essential for connectivity and communication between components, and the power supply provides necessary electrical power, they do not process data themselves. The Graphics Processing Unit (GPU) plays a significant role in rendering graphics and performing complex calculations, particularly in gaming and graphic-intensive applications, but its primary focus is not general-purpose data processing. Thus, among the options provided, the CPU is clearly the component that has the most direct responsibility for processing data.