The correct answer is: C. Monitors the flow of information.
The control unit is the part of the CPU that fetches instructions from memory, decodes them, and then directs the ALU and other parts of the CPU to carry out the instructions. It also controls the flow of data between the CPU and other parts of the computer.
Option A is incorrect because the ALU communicates its results to the control unit.
Option B is incorrect because the control unit activates the output device, not the ALU.
Option D is incorrect because the control unit does not control the printer. The printer is controlled by the output device.
Option E is incorrect because the control unit does monitor the flow of information.