You observe that your friend has dimples. dimples result from the presence of the dominant gene d; absence of dimples is a homozygous recessive condition (dd). what genotype or genotypes might your friend have

DD or Dd

Explanation:

Dimples is the dominant trait (D). Your friend has dimples so that means he or she should have at least one allele of the dominant trait to express that trait. So your friend would either be homozygous dominant (DD) or heterozygous dominant (Dd). Notice that there is a recessive allele in the second. Even with that present, dimples would be still expressed.