When creating and modifying templates, which keys are used to add placeholders? Alt+F9
Shift+F8
O Delete+F8
Ctrl+F9

On the Slide Master tab, click Insert Placeholder, and then click the type of placeholder that you want to add. Click a location on the slide layout, and then drag to draw the placeholder. You can add as many placeholders as you like. (For Power point) But not sure about a short cut for it. Hope this helps!

Insert Placeholder

Explanation:

answer; i believe the correct answer is (a) all trenches must have access/egress;