The answer is b, for he is comparing the two rocks to find an age relative to the other
Chloroplast is responsible for using light energy to produce sugar. It is located at the top of the leaf because that's where it will absorb the most light while it's still being protected from damage by the cuticle and the epidermis
Moistens tissues especially those that belong to the eye, the nose and mouth.
Water in the body also regulates body temperature.
It transports oxygen and nutrients to the cells.
It also helps to prevent constipation.