Answer:
c. No, for each height, there are people of different ages.
Explanation:
We say that y is a function of x when there is a relationship between x and y. For example, the distance you run on a single day and your average speed.
However
There is no relationship between age and height. For example, we may both be the same age and have very different heights.
So the correct answer is:
c. No, for each height, there are people of different ages.