Options are:
(A). emissions;
(B). dangerous;
(C). bent;
(D). homogenous;
(E). antigens;
(F). vehicles;
(G). fossil fuels;
(H). heat energy;
Q: Fact 1: Antigens are molecules that the immune system recognizes as foreign to the body. Fact 2: Heavy metals are, in general, foreign to the body. Given the two facts above, heavy metals are _.?
A:
(E).