Fact 1: Sperm had to swim from male to female reproductive organs for fertilization.

Fact 2: Sperms swim with their tails.

Given the two facts above, answer the question "Something that swims from male to female reproductive organs for fertilization uses what to move?" with the following options: 
- Energy
 - Tail
 - Brain
 - seeds
 - Legs
 - Arms
 - a path
 - heat


 

  Tail       