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
Ventricular contraction lasts for: 
Select and explain. 
A. Beginning of Q wave to end of S wave, B. Beginning of Q wave to the end of T wave, C. Beginning of P wave to end of T wave, D. Beginning of R wave to the end of T wave, if Q wave is absent
B: Beginning of Q wave to the end of T wave
Answer: B: Beginning of Q wave to the end of T wave 
Explanation: B i.e. Beginning of Q wave to the end of T wave