Which statement best describes incomplete dominance?

• A. Heterozygotes display the same phenotype as one of the homozygotes.
• B. Heterozygotes show an intermediate phenotype between the two homozygotes.
• C. One allele completely masks the other in heterozygotes.
• D. Each allele contributes to the phenotype in a dosage-dependent way but not an intermediate color.

Answer: (B)

Incomplete dominance occurs when neither allele is completely dominant over the other, so the offspring with one of each allele displays a phenotype that’s between the two homozygous phenotypes. This is exactly what the chosen statement describes: the heterozygote has an intermediate phenotype between the two homozygotes. A classic example is red and white flowers producing pink flowers in the heterozygous offspring. If the heterozygote looked like one parent, that would be complete dominance; if it showed both traits at once, that would be codominance. The idea that each allele adds a dosage effect without an intermediate color describes a different pattern and doesn’t capture the blending aspect of incomplete dominance.