if you encounter a hostile questioner while giving a presentation, you should avoid

There are several ways to avoid confrontation from a hostile questioner while giving a presentation. 

You can discourage interruptions by setting limits on when you will take questions. To avoid being confrontational or authoritarian, state why the limits benefit your audience and ask for their approval.

When dealing with a confrontational question, separate the attitude of the questioner from the content of the question.

The least confrontational way of dealing with a constant stream of questions is to answer each question as briefly as possible. Limit your answers to one breath in length.