When giving a presentation, you'll most likely be asked several questions. One of the most important parts of the question and answer portion is for the speaker to repeat the question so everyone else can hear it.
Sometimes a question will be asked by a person in the front row and a speaker will answer without anyone behind the asker understanding the question. Sometimes a question will be asked by a person and the presenter will respond with an answer that doesn't relate to the question.
For these reasons, you must repeat any question that is asked. Even if the person asking the question has a microphone. For the following reasons:
Helps the entire audience hear the question
Repeating the question ensures that everyone in the audience hears the question. Especially if your presentation is being recorded, it makes sure that the question AND answer are together.
Helps make sure you understand the question
Every once in a while, what you hear is not what the asker meant to say. Repeating the question gives them an opportunity to clarify the question so you don't spend 5-minutes answering a question they didn't ask.
Helps give you a moment to collect your thoughts
Repeating the question gives you time to formulate an answer. If you aren't sure at first, repeating the question gives you a chance to scan your brain for what to say. Instead of a 15-second blank pause, it would just be 2 or 3-seconds.
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