All of the Following Have Been Suggested as Methodological Flaws

All of the following have been suggested as methodological flaws in LeVay's studies correlating the hypothalamus with homosexuality

A) AIDS is what altered the structure of the hypothalamus.
B) LeVay did not ascertain the sexual orientation of his population of straight men. Some of them could have been gay.
C) Perhaps being gay alters the structure of the hypothalamus; it is an effect rather than a cause.
D) LeVay's population of gay women, a control group, was larger than his population of gay men introducing statistical concerns.