The correct answer is 'B. Arithmetic logic unit, Control unit' because these two components are essential parts of the CPU. The Arithmetic Logic Unit (ALU) is responsible for performing arithmetic and logical operations, while the Control Unit is responsible for coordinating the activities of the CPU, fetching instructions, decoding them, and executing them. Together, the ALU and Control Unit work together to carry out the instructions of a computer program, making them integral components of the CPU.