The correct option is D Control
The control unit is entrusted with the responsibility of controlling and coordinating the activities of all other units of the computer system. Specifically, it performs the following functions:
a. Read instructions out of memory unit;
b. Decode such instructions;
c. set up the routing of data, through internal circuitry/wiring to the desired place at right time; and
d. Determine the input device from where to get next instructions after the instructions in hand has been executed.