Question

Which of the following selection types shifts the mean of a continuous phenotype such as size or length?
A. Artificial selection
B. Directional selection
C. Disruptive selection
D. Neutral selection
E. Stabilizing selection

Answer 1

When the environmental condition changes, populations can typically endure this sort of choice, that selects for phenotypes at one finish of the spectrum of existing variation. A classic example of this sort of choice is that the evolution of the peppered lepidopteran in eighteenth- and nineteenth-century European countries.

Complete answer:
Artificial selection is a synthetic mechanism for evolution to occur. It is most commonly seen with the careful breeding of various plants or animals to market traits that are suitable for human preferences. In this case, it's substitutable with a lot of widely used phrase selective breeding. It contrasts with natural selection in that it's intentional and guided.
-Directional selection tends to shift the distribution curve in one direction thereby ever-changing the typical value of the character. This is often a result of why directional selection favors phenotypes at (one in every ) the extremes in a statistical distribution and over-ordered generations, one composition or one phenotype can be replaced bit by bit with the opposite.
-The disruptive selection conjointly referred to as diversifying selection, describes changes in population genetically during which extreme values for an attribute are favored over intermediate values. 2 peaks are observed however no sub-population is made during this case.
-Phenotypic variation represents the variability in the composition that exists in a very large population and is the necessity of evolution through the method of neutral selection. This type of selection doesn't act directly on the organism's genotype however on the phenotype.
-Stabilizing selection is the opposite of disruptive. Rather than affirmative individuals with extreme phenotypes, it favors the intermediate variants.

Hence, B is the correct answer.

Note: Directional selection is one kind of natural process during which the phenotype or composition (the discernible characteristics) of the species tends toward one extreme rather than the mean composition or the alternative extreme composition.