Not 100% sure but B sounds the most likely from what I've read...
Answer:
Zinc
Explanation:
Zinc deficiency is a condition in which the amount of zinc present in the body is low. It means there is not enough quantity of zinc in the body that is needed to carry out various functions.
Zinc deficiency could lead to hair loss, skin rashes, poor vision, growth problems, weight loss, inability to taste well, loss of apetite.
It is therefore necessary to take the right amount of zinc present in foods like meat, legumes, nuts, egg, milk.
Your answer would be water , the body needs to have plenty of water
