Which genotype corresponds to two dominant alleles?

• A. Homozygous
• B. Homozygous Dominant
• C. Heterozygous
• D. Sex-linked trait

Answer: (B)

The genotype here refers to the two alleles a person has for a single gene. When both copies are the dominant variant, the organism is homozygous dominant. In a typical A vs a system, that means the genotype is AA. The term homozygous means the alleles are the same, and adding “dominant” specifies that both copies are the dominant form, which is exactly what two dominant alleles represent. If there were one dominant and one recessive allele, that would be heterozygous (Aa). If both copies were recessive, it would be homozygous recessive (aa). The idea of a sex-linked trait is a separate concept about whether the gene is on the sex chromosomes and does not describe having two identical dominant alleles.