Difficult questions tend to be emotional because the asker is usually frustrated or anxious.

The way you hold your body is as important as your tone.

When you're faced with difficult questions, make sure you buy yourself enough time to determine how you want to respond.

Acknowledge the question, but then divert the conversation to a different topic, one you are more comfortable approaching and that interests you more.

Buy yourself some time by stating that you don't currently have enough information to provide a solid answer.

Make sure you maintain a polite tone, even if you refuse to answer the question.

Find a part of the question you are comfortable answering if answering the whole question is not an option.

Turn around the pronouns to shift the focus on the other person and take it off of you.