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: Medicine
Which of the following is the most important bedside measurement from which volume status can be assessed 
Select and explain. 
A. JVP, B. ECG, C. Pulse rate, D. None of the above
A: JVP
Answer: A: JVP 
Explanation: JVP is the single most important bedside measurement to estimate the volume status. The internal jugular vein is preferred because the external jugular vein is valved and not directly in line with the superior vena cava and right atrium.