Answer:
When we rotate a point A, around point C, the distance between the points is invariant.
This means that if A' es the image of the rotated point, then A' must lie in a circle centered in C with radius AC.
Then the correct statements are:
A' lies on a circle centered at point C with radius AC
This is by definition.
m∠ACA' = 90°
This is because A is rotated 90° around C to form the image A', then the measure must be 90°.
AC = A'C
As we already defined, the distance between the rotated point and the center of rotation is invariant, then the distance between A and C must be the same as the distance between A' and C.