Which of the following is the combining form for 'vein'?

• A. Angio-
• B. Ven/o
• C. Phleb/o
• D. Vas/o

Answer: (C)

Vein-specific roots come from Greek, and the standard combining form for vein is phleb/o. It comes from phleps, meaning vein, and shows up in terms like phlebitis (inflammation of a vein) and phlebotomy (puncture of a vein). Angio- refers to a vessel in general, not limited to veins, while vas/o is another vessel-related root used in broader contexts. (Note that ven/o also relates to a vein, but phleb/o is the traditional and most specific form for “vein” in many medical terms.) This is why phleb/o is the best choice for the combining form of vein.