Which process describes the fertilization of an egg by sperm within the body of a female?

The process of fertilization that occurs within the body of a female is known as internal fertilization. This method involves the sperm being deposited inside the female's reproductive tract, where it can then fertilize the egg. Internal fertilization is common in many animals, including mammals, birds, and some reptiles, and it allows for a more controlled and protected environment for the developing embryo.

In contrast, external fertilization occurs outside the female's body, typically in aquatic environments, where eggs and sperm are released into the water. Asexual reproduction does not involve fertilization at all, as it refers to reproduction without the combination of male and female gametes, resulting in offspring that are genetically identical to the parent. Binary fission is a form of asexual reproduction observed in single-celled organisms, where the parent organism divides into two identical daughter cells.

Understanding these differences highlights why internal fertilization is specifically characterized by the fertilization process taking place within the female, ensuring a higher chance of successful reproduction.