The correct answer is: A. storage unit
The CPU (Central Processing Unit) is the main part of a computer that carries out instructions. It is made up of three main parts: the arithmetic and logic unit (ALU), the control unit, and the registers.
The ALU is responsible for performing arithmetic and logical operations, such as addition, subtraction, multiplication, and division. The control unit is responsible for fetching instructions from memory, decoding them, and executing them. The registers are temporary storage locations that hold data and instructions that are being processed by the CPU.
The storage unit is not a part of the CPU. It is a separate component that stores data and programs that are being used by the CPU. The storage unit can be either a primary storage unit, such as RAM (Random Access Memory), or a secondary storage unit, such as a hard drive.
RAM is a volatile memory, which means that it loses its contents when the power is turned off. Hard drives are non-volatile memories, which means that they retain their contents even when the power is turned off.
The storage unit is important because it allows the CPU to access data and programs quickly. Without the storage unit, the CPU would have to access data and programs from the input/output devices, which would be much slower.
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