Which of the following properties do not change under a

size transformation? Explain how you can be sure of your
answers.
a. Distance between points
b. Angle measure
c. Parallelism; that is, if two lines are parallel to each
other, then their images are parallel to each other.

c. is right. But note that:

Which of the following properties do not change under a
size transformation?

It is a very subtle question. The verb "do" means that there may be more than one answer. Can you spot the other?