The author used a question-and-answer format to develop the main points of the passage to guide readers' understanding of a complex topic. That is option A.
What are rhetorical questions?
Rhetorical questions are those questions that are used by authors in their literature for clarification and not for a direct answer to be given.
From the excerpt, the questions that where asked is an example of rhetorical questions about clock of which the author gave clear answers to.
Therefore the author used a question-and-answer format to develop the main points of the passage to guide readers' understanding of a complex topic.
Learn more about rhetorical questions here:
https://brainly.com/question/13734134
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