In the First Phase of Triggering an Action Potential in a Neuron

Multiple Choice

In the first phase of triggering an action potential in a neuron, Na⁺ ions flow in and

A) only trigger a negative feedback loop.
B) only trigger a positive feedback loop.
C) only activate the sodium/potassium pump.
D) trigger a negative feedback loop and activate the sodium/potassium pump.
E) trigger a positive feedback loop and activate the sodium/potassium pump.