Answer the following question given this paragraph: 

Fertilization The fusion of a sperm and an egg is a process called fertilization. This can occur either inside ( internal fertilization) or outside ( external fertilization) the body of the female. Humans provide an example of the former, whereas frog reproduction is an example of the latter.


Q: What is the process of the fusion of a sperm and an egg called?

 Choices:

- Sperm

- embryo

- stimulation

- fertilization

A:
fertilization
