A verb in the indicative mood is one that expresses a statement of fact or belief.
In the passage provided, Sentence 20 contains a verb in the indicative mood: "The Grand Canyon is visited by almost five million people each year."
Therefore, the correct answer is: Sentence 20 (Note: since this specific sentence was not listed in your options, the closest indicative mood sentence from your options would be Sentence 22: "If I had the chance, I'd go," but it's conditional, not purely indicative. Please confirm if you have a set of available options or need factual confirmation on a specific one.)