PT 64 S1 Q22

Microbiologist: Because heavy metals are normallyconcentrated in sewage ... ...

Which one of the following, if true, most strengthens the microbiologist’s argument?
(A) Most bacteria that are not resistant to antibiotics are not resistant to heavy-metal poisoning either.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Oct 2011 LSAT (PT 64): Logical Reasoning A