This electrical shift, which lasts about a millisecond, is called the potential.

action potential

Explanation:

Action potential -

In the model of Hodgkin–Huxley , also known as the conductance-based model.

This model helps to explain that how the action potentials in the neurons are initiated and then propagates .

Action potential , refers to the electric shift that , which lasts for around a millisecond .

Hence, from the given statement of the question,

The correct term is action potential.

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."