How do you react when people criticize your work or question your opinions? Are you able to keep calm or do you tend to lose your temper?
People love a good argument, whatever the subject. It seems to be a part of human nature.
For this reason you must be prepared to deal with disagreement.
There are about three kinds of objection you might face:
Fair criticism that reveals weaknesses in your work or facts that you cannot dispute. Accept the criticism and thank the questioner. Point out that it will contribute to correcting and improving your work.
Objections that are not based on proven facts, but which are simply the questioner’s own opinion. They are legitimate but cannot affect the correctness of your work. Politely disagree, say why you think you are right and support your position by citing facts and reliable sources.
Objections which are irrelevant or off-topic. Just point out that, even though the criticism is interesting, it has no relation to your presentation and so you are unable to answer.
And remember, even in situations where someone is trying to give you a hard time, always keep calm and behave professionally.