What are the male reproductive organs in animals responsible for sperm production?

The correct answer is the testes, which are the primary male reproductive organs responsible for the production of sperm. The testes function not only to produce sperm through a process called spermatogenesis but also to produce male hormones, primarily testosterone, which is crucial for the development of male secondary sexual characteristics and the regulation of sperm production.

In the reproductive system, the testes are typically located outside the body in a pouch called the scrotum, which helps maintain an optimal temperature for sperm development, as sperm production requires a temperature slightly lower than that of the body's core.

The other options are not involved in sperm production. Ovaries are the female reproductive organs that produce eggs, not sperm. Prostates play a role in the male reproductive system by producing fluid that nourishes and protects sperm, but they do not produce sperm themselves. The vas deferens is a duct that transports sperm from the testes to the urethra but does not have a role in their production.