Answer: The answer is (A) CD.
Step-by-step explanation: We are given to choose the correct option that represents the distance from point D to AB.
We know that the distance between a point and a line is the length of the perpendicular drawn from the point to the line.
So, here CD will be the required distance from point D to AB, because CD is perpendicular from point D to AB.
Thus, (A) is the correct option.