Question: Looking at your results of the Ames test , using bacteriological agar medium plates lacking the a…

Looking at your results of the Ames test , using bacteriological
agar medium plates lacking the amino acid histidine, you find that
there are many colonies growing on the agar. Your interpretation of
this result is:

A. The bacterium has turned its operon genes on, producing
proteins necessary for growth

B. The chemical being tested is mutagenic

C. The bacterium does not have any plasmids, so it cannot grow
on the medium

D. The drug being tested has no inhibitory effect on the
bacterium, therefore it is not a good antibiotic to give for
treatment of disease