Explanation:

The Central Processing Unit (CPU) is the component responsible for performing all arithmetic operations (like addition) and logical operations (like comparison). Specifically, the Arithmetic Logic Unit (ALU) within the CPU handles these tasks. (a) Hard disk is a long-term storage device. (b) Monitor is an output device. (c) Memory chip (e.g., RAM) stores data and instructions temporarily for the CPU to access, but it does not perform calculations or comparisons itself. (d) CPU chip (microprocessor) contains the ALU, which is where data is added and compared. Therefore, the CPU chip is the correct location.