Answer:
A and B
Explanation:
Kinetic energy is when an object is in motion, and potential energy is kind of when an object stops being in motion, or there is a pause in motion for an extent of time.
When you are holding the book before dropping it, that book is at potential energy. When you drop the book, the book gains kinetic energy as it falls from your hands and hits the floor. Once it hits the floor and rests, it regains potential energy.
I hope that this helps.