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
All of the following factors normally increase the length of the ventricular cardiac muscle fibers except: 
Select and explain. 
A. Increased venous tone., B. Increased total blood volume, C. Increased negative intrathoracic pressure., D. Lying-to-standing change in posture
D: Lying-to-standing change in posture
Answer: D: Lying-to-standing change in posture 
Explanation: D i.e. Lying to standing change in posture When a person moves from a supine position to standing position volume of blood pools in the lower extremity because of high compliance of veins & venous return decreases. As a result of decreased venous return the length of ventricular cardiac muscle fibres is decreasedQ and so the cardiac output in accordance with frank-sterling law.