Which of the following best predicts the response of a trait to artificial selection?

VA
VG
standard deviation
h2
H2

It would be clearer if you spelled out the other alternatives beside standard deviation.

The answer is h^2, or narrow sense heritability.

The correct answer is h2 (pronounced "h-squared"). To understand why h2 is the best predictor of a trait's response to artificial selection, let's break down the options and explain each one:

1. VA (Additive Genetic Variance): This option refers to the genetic variation within a population that contributes to the variation in a specific trait. While VA influences trait expression, it does not accurately predict how a trait will respond to artificial selection.

2. VG (Genetic Variance): This option denotes the total genetic variation within a population for a given trait. Like VA, VG is not the most precise predictor of a trait's response to artificial selection.

3. Standard Deviation: Standard deviation is a statistical measure that calculates the dispersion of values around the mean of a dataset. Though it provides useful information about the variation within a trait, it does not directly indicate how the trait will respond to artificial selection.

4. h2 (Heritability): Heritability (represented as h2) is the proportion of the total phenotypic variation in a trait that is attributed to genetic variation. In other words, it quantifies the extent to which genes contribute to phenotypic differences in a population. As a measure of the proportion of genetic variation in a trait, h2 is the best predictor of how a trait will respond to artificial selection.

5. H2: It is assumed that this is a typo or a misrepresentation of h2, as mentioned earlier. h2 is the correct term used in genetics to represent heritability.

Therefore, h2 is the most appropriate choice among these options when it comes to predicting the response of a trait to artificial selection.