For starters, humans have feelings and cells. If we get hurt we can feel things such as pain unlike a tent. If you hit a tent there is nothing it feels because it has no feelings. We have cells all through our body and rocks don't. They are made of other stuff but not cells.
D. Focusing
Sound waves reflected in flat surfaces like walls, floors and ceilings results to uneven dispersion of sounds by creating locations with high intensity and another with low intensity. This process is called Focusing and can be undesirable in auditoriums.
I believe the candy bar increases blood sugar levels, so the body has a bit too much energy and tries to keep you moving to help burn it off or something. Sorry, not too sure