Suppose That an Allele Is Present in Blue-Footed Booby Offspring

Multiple Choice

Suppose that an allele is present in blue-footed booby offspring that causes a nestling to share its food with its nestmate if it is not particularly hungry during times of adequate food availability. This gene imposes a fitness cost of 0.3 on those who carry it, while conferring a benefit of 0.4 on the sibling who receives the additional food. Will this gene increase in frequency if the two nestmates are always half siblings (with the same mother but different fathers) ?

A) Yes, because rb  c < 0.
B) Yes, because rb  c > 0.
C) No, because rb  c > 0.
D) No, because rb  c < 0.