How to Handle an Uncomfortable Situation
This only happens on very rare occasions. But no matter what happens, keep your cool. If you get a hostile question or comment, thank the person for sharing his thoughts with you, then deal with it just like you would handle an objection. If the whole room starts twitching in their seats, stop your pitch and ask them if you've said something wrong, then correct your misstatement.
Excerpted from Creative Selling: Boost your B2B sales