You are presented with the question "What happens inside the single egg embedded inside the prothallus " and the following answer choices: 
- Earth revolving around the sun
 - The area was once underwater
 - gastropod shells
 - it keeps an organism warm
 - remains of prehistoric life
 - fertilization occurs
 - allow growth
 - It helps them survive

Now knowing that fertilization occurs when sperm swim to an egg inside an archegonium and each archegonium contains a single egg that is embedded in the prothallus, choose the best answer.


 

      fertilization occurs   