How do vitamins keep the body healthy?
increase ldl cholesterol levels
raise blood sugar levels
boost fat cell production
boost the immune system and heal wounds

How do vitamins help keep the body healthy?

boost the immune system and help heal wounds

Communication. releasing emotions/feelings to someone you know you can count on. ; ) someone who may not understand but willing to listen.

(a) is not correct because one does not get increased cholesterol  from lifting weights.(b) is not correct because lifting weights cannot reduce the risk of a hereditary disease.(c) is not correct because back pain isn't a benefit! and plus, if he lifts weights properly, he should not have back pain.(d) is the correct answer because his ligaments will gain mass, making it easier for him to carry heavier weights and he will also be stronger!