Which statement best defines venous insufficiency?

• A. Arteries narrow causing reduced perfusion
• B. Valves located within the vein become insufficient and blood flows in reverse direction
• C. Lymphatic flow blocked causing edema
• D. Heart valves malfunctioning

Answer: (B)

Venous insufficiency is about the veins’ valves failing to close properly, so blood can flow backward (reflux) and pool in the legs. Veins rely on one-way valves to stop backflow as blood is moved toward the heart. When these valves become damaged or incompetent, standing or muscle relaxation allows blood to reverse direction, raising venous pressure, causing swelling, varicose veins, and related symptoms. That description—valves within the vein becoming insufficient and blood flowing in reverse direction—precisely matches the condition.

The other scenarios describe problems in different systems: narrowing of arteries reduces blood flow to tissues (arterial disease), lymphatic blockage leads to lymphedema, and heart valve problems affect the heart's pumping and circulation rather than the venous valves themselves.