Question

When the mean value of variation is selected AGAINST, ____ selection results.

disruptive
directional
stabilizing
no

Answer 1

Disruptive selection results. 

Answer 2

Stabilizing selection.

Step-by-step explanation:

Stabilizing selection may be defined as the type of natural selection in which the mean population stabilizes for a particular trait. The theory of stabilising selection was given by Ivan Schmalhausen.

Stabilizing selection doesnot select against the extreme phenotype but the mean variant is selected in the population. This selection shows the negative selection in a population.

Thus, the correct answer is option (3).