Select the Correct Statement About Fertilization

Select the correct statement about fertilization.

A) If estrogen is present, the pathway through the cervical opening is blocked from sperm entry.
B) Both spermatozoa and the ovulated secondary oocyte remain viable for about 72 hours in the female reproductive tract.
C) Millions of sperm cells are destroyed by the vagina's acidic environment.
D) Once inside the uterus, most sperm cells are protected and remain viable.