Answer:
Because if they mate with another carrier of the recessive trait, then the offspring is at risk of having the trait.
Explanation:
Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light.In other words, brightness is the perception elicited by the luminance of a visual target. This is a subjective attribute/property of an object being observed and one of the color appearance parameters of color appearance models.
The answer to your question is, competent person
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