15. protein is essential to the overall health of the body because it a. sustains life and keeps body systems in good repair. b. "bulk up" muscles. c. keeps hair and nails healthy. d. gives the body collagen, which protects the organs.

Ibelieve the answer is d.

Dis correct. the rest of the answers are definitely wrong.without the basic needs like food, shelter and love , one will remain trapped in trying to fulfil these needs first which means putting food on the table and struggling to pay bills. it is impossible to achieve self actualization when without the basic needs which is the base.