, the brains of a computer, it contains the ALU, the clock, many registers, the bus i

, the brains of a computer, it contains the ALU, the clock, many registers, the bus interface, and circuitry that makes these pans work together.

A．I/O device

B．CPU

C．Memory

D．Operating system

请帮忙给出正确答案和分析，谢谢！