Question

Over the years, there has been an overuse of antibiotics. This overuse has resulted in more less resistant and weaker bacteria to die off, while the more resistant bacteria are surviving. These survivors are sometimes called superbugs. What type of selection would this represent?
A.stabilizing selection
B.directional selection
C.disruptive selection
D.normal distribution​

Answer 1

Answer:

The correct answer is - B.directional selection.

Explanation:

When a bacterial colony is exposed to an antibiotic the maximum number of the bacteria dies due to noo resistane and some of survive even with no or very less resistance to the antibiotic and reproduce.

Over many generations  the survived and continuosuly divivng resitant bacteria become more and more with higher frequency and ultimately evolved to a resistance strain of the bacteria for the antibiotic. Such mutation is directional selection as the frequency of the resistance bacteria going from no resistance to a high amount of resistance is unidirectional and progresive.