Is "Clip Art" A Good Choice For Professional Presentations?

Yes it is a good idea to include clip art in Professional Presentation. But try to use the open which goes with your topic. Some people add these clip arts just to grab audience attention. Or when the audience is getting bored the presenter made a comment on these clip arts to grab their attention. Some might use animated one just to make presentation lively. It is better not to use too much clip arts in your presentation. But all depends how you present it.

Yes. The quality of clip art and the types available now make them a good choice for Art and graphics in all types of presentations. Good Visual is a good part of any professional presentation, and makes it much more memorable.