In a cross between a homozygous dominant and a homozygous recessive, which statement best describes the offspring?

• A. All offspring are heterozygous and display the dominant phenotype.
• B. All offspring are homozygous and display the dominant phenotype.
• C. Offspring are 50% heterozygous and 50% homozygous recessive.
• D. Offspring are 25% heterozygous and 75% homozygous dominant.

Answer: (B)

Crossing a homozygous dominant individual with a homozygous recessive one shows how alleles segregate and how dominance works. Each offspring gets the dominant allele from the first parent and the recessive allele from the second, so every offspring is heterozygous (one dominant, one recessive). Because the dominant allele is expressed, all offspring display the dominant trait. The other described patterns would require different parental genotypes: to get homozygous dominant offspring you’d need both parents to contribute a dominant allele, and to get a mix like 50% heterozygous and 50% homozygous recessive you’d need a cross involving a heterozygous parent.