Penicillin is an antibiotic that was discovered in 1928. Today many species of bacteria have acquired resistance to penicillin. This adaptation occurred as a result of

Answer:
THE ANSWER IS C ( genetic mutation) ON USATestPrep because...
Explanation:
Many bacteria have acquired the ability to produce an enzyme called penicillinase, which destroys penicillin. All enzymes are proteins. The ability to produce the new protein penicillinase came from a change in the bacterial DNA: a genetic mutation.