Answer:In the given scenario, Brian uses audience involvement to open his presentation.
Step-by-step explanation:
For the majority of spectators in an audience, paying attention to a presentation for any amount of time can be quite hard. If they do not feel engaged by the speaker, they will lose their attention, and probably will not benefit from the information presented at all. This is why a presentation should have a lot of energy, a defined purpose, and be totally direct (as if the audience was an individual and it was a one-to-one conversation), to involve the audience.