Explain How Using a Combination of Two Antimicrobial Drugs Helps

Explain how using a combination of two antimicrobial drugs helps prevent the development of spontaneously resistant mutants.

A) All drugs work synergistically with each other-that is, their combined effects are far greater than either could achieve individually. Two drugs together helps to eliminate microbes, even if they have developed spontaneous mutations that would confer upon them resistance to the drugs.
B) It is highly unlikely that the microbe might spontaneously develop 2 specific mutations to resist the effects of a pair of drugs. As such, even if one drug is resisted by the microbe, the 2nd drug will eliminate the mutated microbe, thus preventing the development of spontaneously resistant mutants overall.
C) All drugs work antagonistically with each other-that is, their combined effects are far greater than either could achieve individually. Two drugs together helps to eliminate microbes, even if they have developed spontaneous mutations that would confer upon them resistance to the drugs.
D) Drugs can also select for mutations that will enhance the activity of another drug. So, each of the paired drugs will help to select for spontaneous mutations that enhance the activity of the other drug in the pair.