What is the function of the epididymis?

The function of the epididymis is primarily to store sperm until they are mature. As sperm are produced in the testes, they migrate to the epididymis, where they undergo a maturation process that can take several days. During this time, the sperm gain the motility and capability necessary for fertilization. The epididymis also plays a role in the concentration and storage of sperm, allowing them to be stored until ejaculation.

The other options present functions that are not related to the epididymis specifically. The secretion of testosterone, for instance, is primarily a function of the Leydig cells located in the testes. Holding the testes occurs within the scrotum, and the passageway from the penis to the urethra does not pertain to the epididymis but rather concerns the male reproductive tract as a whole. Thus, the role of the epididymis in storing and maturing sperm is a distinct and critical function within the male reproductive system.