For convenient self-testing, practice quizzes are available for all the modules

There are a number of environmental theories suggesting that childhood experiences contribute to the cause of same-sex sexual attraction. The textbook concludes that

a. No matter how hard researchers have looked, they’ve found no childhood events or activities that are reliably related to later bisexual, lesbian or gay attractions in adults. b. A good deal of evidence points to several early childhood events that may contribute to becoming gay, but not to becoming bisexual or lesbian. c. Several recent studies point to indications that early childhood experiences may contribute to one becoming lesbian, but not bisexual or gay. d. There is a good deal of sound, recent research that points to several childhood factors that likely contribute to gay, lesbian, and bisexual development.

The maternal immune hypothesis suggest that a male child could be predisposed to homosexuality when

a. his H-Y antigens cause his mother to release too much estrogen, exposing his fetal brain to feminization. b. his mother’s antibodies attack his H-Y antigens, preventing the fetal brain from developing male-typical brain structures. c. a fetus develops an immunity to the effects of maternal testosterone, preventing masculinization of his brain. d. his mother is exposed to certain vaccines that increase her immune response, preventing certain fetal structures that are central to a masculine brain from developing.