For traits controlled by a single genetic locus, dominant phenotypes are expected

True.

Explanation:

The dominant phenotypes are expected to occur at a frequency of approximately 75%, in a population because of its dominant nature which allows them to appear in the physical structure of the organisms. In most of the offspring, the dominant allele shows their characteristics in the population whereas the recessive allele are hidden in that organisms and we can't see them in the physical appearance of the organisms.

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