What does it mean that energy is neither created nor destroyed

Energy can only be transformed. You cannot destroy energy or create it. For example, the potential energy when you have something sitting on a desk doesn't disappear once it falls off. It gets TRANSFORMED into kinetic energy. This happens constantly. Energy, the ability to do work or cause a change, is always being reused in different forms. Hope this helped!

C) reflection (i also looked up the other choices just to make sure)

From our previous experiment, we examined how many drops a penny can hold - and place drops of salt water on the penny after recording 5 trials each, take the average of each solution.