If a carbon atom is bonded to two hydrogen atoms and two carbon atoms ,what type of bond must exist between the carbon

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.

According to edgenuity, the answer is c.