What does the urethra primarily facilitate in both males and females?

The urethra primarily facilitates the transport of urine from the bladder to the external environment in both males and females. In males, the urethra also serves the dual purpose of transporting semen, but its primary function is still the passage of urine. In females, the urethra is shorter and exclusively designed for urine transport. This distinction highlights that while the urethra has other functions in males, its primary role across both genders is the elimination of urine.

The other options revolve around functions that are either specific to other systems or organs. For example, the production of sperm is a function of the testes in males, while the secretion of hormones pertains to glands such as the endocrine system. The storage of urine occurs in the bladder, not the urethra. Thus, the primary and most accurate role assigned to the urethra is the transport of urine.