Final answer:
The term 'vas/o' means vessel, vas deferens, or duct, referring to structures in both the circulatory and male reproductive systems, with the vas deferens being a key component in sperm transport. The option (3) is correct.
Step-by-step explanation:
The combining form (CF) vas/o refers to a vessel, vas deferens, or a duct, specifically within the context of the anatomy and functions related to the circulatory and the male reproductive systems. The vas deferens are a vital component of the male reproductive system, playing a crucial role in the transportation of sperm from the epididymis to the ejaculatory duct.
This duct is also sometimes called the sperm duct. Meanwhile, terms such as vasoconstriction and vasodilation relate to the changes in vessel diameter, contributing to the regulation of blood flow and pressure within the vasculature. Thus, the correct answer to the CF vas/o meaning is 3) vessel; vas deferens; duct.