A. confident speech and interactive body language
Body language can make all the difference when doing a presentation. Without body language and confident speech, your presentation could turn dull and static, and most likely won't catch the viewer's attention as much as you'd like it to.
But, by using facial expressions giving eye contact, showing posture, gesturing, and slight movement and changing of position once in a while, you can engage the reader and make the presentation more dynamic.
Confident speech also really helps because, if you were to speak soft and slow, your viewers would be bored and unenthused. When you have a powerful voice and pronounce the words with enthusiasm, you can really catch their attention and make your presentation much more intriguing.