Accidental Deletion of a Slide

Is it possible to prevent theremoval of an data or a slide all together in a Keynote presentation. the situation is that the presentation that I have spent many hours on will be presented by another person using my pe=resentation on my Macbook Pro Retina. The person is not that familiar with Keynote and I would like to prevent the accidental deletion of data or a slide itself by accidentially hitting the Delete Key. I do have the program backed up on a portable hard drive.

Thanks in advance for any suggestions.