In humans, the allele for attached ear lobes (e) is recessive to the allele for free ear lobes (E).

If both of Lisa's parents have attached ear lobes, then
A.
Lisa must have free ear lobes.
B.
Lisa must have attached ear lobes.
C.
Lisa may have either attached ear lobes or free ear lobes.
D.
Lisa must have her ears pierced.

C. Lisa may have either attached ear lobes or free ear lobes.