Answer:
The best answer to the question: What is the maximum frequency at which a neuron could fire action potentials, (taking into account that an action potential lasts from the beginning of the rising phase to the point of maximal undershoot), would be: 430 events per second (Hz).
Step-by-step explanation:
The reason for this being the answer comes from the explanation given in the question itself, when first they give us the information that an action potential, especially in myelinated neurons, takes time first to be generated, to reach firing point and then to be propagated. That is without mentioning the time it takes the neuron to be ready to fire a new action potential. The information says that the neuron can only fire one action potential at a time, and even if the refractory period is taken as negligible, there are only so many times that a same neuron can deporalize and generate action potentials repetitively. This number of events produced, per second, would be, given the conditions set by the question itself, 430 event per second (Hz).