Using the diagram (which I will explain), at which two points has the skydiver reached free fall?
A. A and B
B. B and C
C D and A
D B and D
Ok so, on A and B, you could see the skydiver being dropped out of the plane, the B part of A and B, you could see him moving faster, which I think is when he reached free fall.
Based on your description, it seems that points A and B represent the moments when the skydiver is dropped out of the plane. If the skydiver is in free fall, it means that there is no net force acting on them other than gravity. Therefore, the skydiver would be in free fall starting from the moment they are dropped out of the plane until they deploy their parachute.
So, the correct answer would be A and B.