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': 'Phase 2 of the action potential is due to? \nSelect and explain. \nA. Sodium influx, B. Potassium influx, C. Calcium influx, D. Chloride influx', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) Calcium influx(Ref: Ganong, 25th ed/p.521)In ventricular action potential, Phase 2 is the plateau phasePhase 2 is due to calcium influx', 'role': 'assistant'}]