How can we explain the motion of objects?

All things move based on how much mass they have and it’s relevance to gravity/distance from the ground. As objects moved, force is moving them. An example would be a wagon on a hill. If the wagon is on wheels at the top of the hill and someone uses force to make the wheels move, the wagon will roll down the hill due to inertia and other elements.

There is no reason to think the results are biased or not conducted properly but you should not assume the results are correct just because they were done in a laboratory so the answer would be c. it is likely to be reliable because the results support the conclusion presented.