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
[{'content': 'An action potential is initiated at the Axon Hillock or \xadInitial segment of the neuron because \nSelect and explain. \nA. Threshold for Excitation is lowest, B. Neurotransmitter is released at this site, C. It is an unmyelinated segment, D. Has lowest concentration of voltage gated sodium channels', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]