This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Venous return to heart during quiet standing is facilitated by all of the following factors, except 
Select and explain. 
A. Calf muscle contraction during standing, B. Valves in perforators, C. Sleeves of deep fascia, D. Gravitational increase in arterial pressure
D: Gravitational increase in arterial pressure
Answer: D: Gravitational increase in arterial pressure 
Explanation: With gravitational force while standing, the venous return is reduced.