Question

why should you question a statistics source before using it in your speech?
to ensure the statistic is from a credible source
to ensure it is a biased source that supports your view
to ensure it sounds mysterious from an unknown source

Explanation:

Credible sources provide reliable statistics. Biased or unknown sources may offer inaccurate or misleading data. Using reliable statistics is crucial for a valid and persuasive speech.

Answer:

to ensure the statistic is from a credible source