Among nonmammalian vertebrates, the cloaca is an anatomical structure that functions as

A) a specialized sperm-transfer device produced only by males.
B) a shared pathway for the digestive, excretory, and reproductive systems.
C) a region bordered by the labia minora and clitoris in females.
D) a source of nutrients for developing sperm in the testes.
E) a gland that secretes mucus to lubricate the vaginal opening.