Explanation:

The $\text{Esc}$ (Escape) key is universally used in presentation software (like PowerPoint) to end a slide show and return to the editing view. Option (1) $\text{F5}$ is typically used to *start* a slide show from the beginning. Option (2) $\text{F10}$ activates the menu bar. Option (4) $\text{Space bar}$ is used to advance to the next slide, not to end the show.