Q: Fact 1: Skin is used for protecting the body from harmful substances. Fact 2: Skin is a protective organ. Given the two facts above, what does skin help keep out?

Available options:
(A). medicine
(B). sun's heat
(C). heat
(D). hurtful words
(E). a pathogens
(F). parasites
(G). harmful substances
(H). Echinoderm.
A:
(G).