Final answer:
The measure of the angle formed by a clock is determined by angular displacement, which represents the change in the angle as the clock hands rotate.
Step-by-step explanation:
The measure of the angle formed by a clock is determined by angular displacement. Angular displacement is the change in the angle of an object as it rotates. In the case of a clock, the angle formed by the clock hands moving from one position to another represents the angular displacement.
The direction of the angular displacement depends on whether the clock hands are moving clockwise or counterclockwise. Clockwise rotation results in positive angular displacement, while counterclockwise rotation results in negative angular displacement.
Therefore, the correct answer to the question is D. Angular displacement.