The correct answer is C. CPU chip.
A CPU chip, or central processing unit, is the main processing unit of a computer. It is responsible for carrying out the instructions of a computer program. The CPU chip contains a number of different components, including the arithmetic logic unit (ALU), the control unit, and the registers. The ALU is responsible for performing arithmetic and logical operations, the control unit is responsible for fetching and executing instructions, and the registers are used to store data.
The CPU chip is the most important component of a computer. It is responsible for carrying out all of the instructions of a computer program. Without a CPU chip, a computer would not be able to function.
The other options are incorrect. A hard disk is a storage device that stores data permanently. A floppy disk is a storage device that stores data temporarily. A memory chip is a storage device that stores data temporarily, but it is much faster than a hard disk or a floppy disk.