Which of the Following Is Not Something You Can Do

Which of the following is not something you can do to minimize or avoid problems during a presentation?

A) Number slides or transparencies so you can reorder them if needed.
B) Keep an extra bulb handy in case the projection bulb burns out.
C) Be prepared to give your presentation without visual aids if necessary.
D) Lock all slides in place in the tray,if using 35-mm slides.
E) Adjust the height and width of the screen so that the front half of the audience can see better.