Alejandro, a Twin Who Was Adopted by a Family in Australia

Multiple Choice

Alejandro, a twin who was adopted by a family in Australia, and was given proper nutrition as he grew up. Alejandro's twin brother was not adopted, and continued to live in an orphanage. When comparing the height of the two boys, Alejandro is taller than his brother. What could be the reason for that?

A) Alejandro's allele
B) Alejandro's genotype
C) Alejandro's phenotype
D) Alejandro's heritability