As urban populations continue to grow, so do the number of citizens who burn coal for fuel. Which detail would provide factual support for this sentence?

- Data about the kinds of pollution caused by burning coal.

Explanation:

The authors employ a variety of details and descriptions in order to substantiate their claim and establish its reliability before the readers. These details could be factual or evidential that assist them to persuade the audience and elicit desired response from them.

In the given question, the details regarding the 'data about the types of pollution that are caused by burning of coal' exemplify factual support to author's claim that asserts 'increased urban population would lead to increased burning of coal for fuel'. These statistical details would demonstrate the facts associated with the claim before the audience that would establish the credibility of the author's declaration/claim and convince the audience (logically) to believe in it.

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