Carbon bonding is almost entirely covalent. This property allows carbon compounds to make oxygen more readily available to the organism. The correct option among all the options that are given in this question is the last option. This property of carbon has become a life saver for variety of organisms.
I think it's the evaporation of water through the stomata :)
B. ATP synthase. The purpose of the hydrogen gradient is to take advantage of molecules' tendency to move from areas of higher concentration to areas of lower concentration. ATP synthase lets hydrogen ions flow through it to the matrix, and the energy from this flow is used by ATP synthase to synthesize ATP.
Black skin to better absorb sun rays to help stay warm also fat/blubber to keep body temp warm/stable
