Food chain and food web

Correct answer: A. Dominance is related to expression, not usefulness

The governing concept is the distinction between genetic dominance and biological advantage. A dominant allele is expressed in the phenotype when present in one copy, whereas a recessive allele may require two copies. Dominance describes expression, not whether a trait improves survival or reproduction. Usefulness depends on the environment and selection. Therefore option A is correct; dominance is not itself natural selection, and recessive traits can appear in suitable genotypes.

Correct answer: A. It can pass through generations in hidden form with a dominant form

The governing concept is allele masking in a heterozygous genotype. When a recessive allele is paired with a dominant allele, the dominant phenotype may appear, so the recessive trait is not visible. However, the recessive allele remains in the DNA and can enter gametes. If two carriers reproduce, their offspring may inherit two recessive copies and express the trait. Thus option A is correct.