This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Heart, Circulation, and Blood, Subject name: Physiology
[{'content': 'Depolarization of the ventricular muscles starts at \nSelect and explain. \nA. Left side of the inventricular septum, B. Right side of the septum, C. Apex of the heart, D. AV groove', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A. i.e. (Left side of the interventricular septum) (549- Ganong 22nd) (492- Ganong 23rd)* In humans - depolarization of the ventricular muscle starts at the left side of the interventricular septum** and moves first to the right across the midportion of the septum. The wave of depolarization then spreads down the septum to the apex of the heart* Depolarization initiated in the SA node spreads radially through the atria then converges on the AV node.', 'role': 'assistant'}]