Hello,
The answer is option D "Energy is conserved".
Reason:
The answer to this question is option D because it seems to be the best fit. Its not option A or B because energy cannot be created nor destroyed it only can be transformed into another type of energy. It shouldn't be C because energy is not always increasing because potential energy is the amount a energy that is in a object THATS NOT MOVING....therefore your answer is option D.
If you need anymore help feel free to ask me!
Hope this helps!
~Nonpotrit