Which Outcome Is Consistent with the Fraternal Birth Order Effect

Which outcome is consistent with the fraternal birth order effect?

A) The fewer older biological brothers a boy has, the more likely he is to develop a homosexual orientation.
B) Boys who are only children are more likely to develop a homosexual orientation.
C) The more older biological brothers a boy has, the more likely he is to develop a homosexual orientation.
D) The more siblings a boy has, the more likely he is to develop a homosexual orientation.