Question

question 3
a recessive allele can only appear in the phenotype of an individual
exposed to certain environmental conditions.
who is homozygous for the mutation.
in the f1 generation.
who carries the mutation in his or her gametes.

Explanation:

In genetics, a recessive allele is masked by a dominant allele in heterozygous individuals. Only when an individual is homozygous for the recessive mutation (has two copies of the recessive allele) will the recessive - trait appear in the phenotype. Environmental conditions may influence gene expression but are not the main factor for a recessive allele to appear in the phenotype. The F1 generation can have various genotypes depending on the cross, and carrying a mutation in gametes does not necessarily mean the phenotype will show the recessive trait.

Answer:

B. who is homozygous for the mutation.