Fertilization occurs when sperm swim to an egg inside an archegonium, and each archegonium contains a single egg that is embedded in the prothallus. Given these facts, what happens inside the single egg embedded inside the prothallus  among the following options:
- 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


 

      fertilization occurs   