Besides Chromosomes and Genes, the Other Biological Factor That May

Besides chromosomes and genes, the other biological factor that may determine whether one is attracted to members of the opposite, or one's own, sex is:

A) early childhood experiences.
B) exposure to sex hormones during gestation as a fetus.
C) whether the mother smoked or drank during pregnancy.
D) whether the mother ate meat during pregnancy.
E) whether the fetus was raised by lesbian/gay parents.