It has been suggested that the fraternal birth-order effect is a result of
A) erotic plasticity.
B) refractory periods.
C) a maternal immune response.
D) mass-media norms.

Question

It has been suggested that the fraternal birth-order effect is a result of
A) erotic plasticity.
B) refractory periods.
C) a maternal immune response.
D) mass-media norms.

Quizplus · Accepted Answer

The fraternal birth-order effect is the phenomenon in which the odds of a male child being homosexual increase with each older brother. One possible explanation for this effect is the maternal immune response theory, which suggests that a mother's immune system may become increasingly reactive to certain proteins expressed by male fetuses during pregnancy, leading to an increased likelihood of homosexuality in subsequent male offspring. Therefore, choice C is the best answer.

It Has Been Suggested That the Fraternal Birth-Order Effect Is