Chapter 7, Problem 5RA

Repolarization of an axon during an action potential is produced by

$\begin{array}{l}\text{a}{\text{. inward diffusion of Na}}^{\text{+}}\text{.}\hfill \\ \text{b}{\text{. active extrusion of K}}^{\text{+}}\text{.}\hfill \\ \text{c}{\text{. outward diffusion of K}}^{\text{+}}\text{.}\hfill \\ \text{d}{\text{. inward active transport of Na}}^{\text{+}}\text{. }\hfill \end{array}$