Because of the great loss of spermatozoa during the process of traveling from the vagina to the ampulla of the uterine tube where fertilization occurs, a male must have at least ________ spermatozoa per milliliter, or he will be functionally sterile.
A) 10,000 B) 100,000 C) 2,000,000 D) 20,000,000 E) 500,000,000