The Female Reproductive Tract Helps Sperm Along to the Egg

The female reproductive tract helps sperm along to the egg, but weeds out the less robust sperm. How and why?

A) The female reproductive tract doesn't really help or hinder sperm. It provides the egg and a place for an embryo to attach.
B) The female reproductive tract only helps sperm but contracting and providing mucus for swimming and chemical cues to find the egg. The more sperm that gets in the better.
C) Cervical mucus helps the sperm along but the cervical cap catches weak ones, and then weak ones can't hold on in the oviduct to wait for the egg. Only healthy sperm get a chance to fertilize an egg.
D) Cervical mucus catches weak swimmers initially and only healthy sperm can attach to the oviduct to wait for the egg. Only healthy sperm get a chance to fertilize an egg.
E) The female reproductive tract is so long that only strong sperm can actually make it to the oviduct where the egg is released. Only healthy sperm get a chance to fertilize an egg.