C) The winner of this grueling race, covering more than a thousand miles, becomes famous!
Explanation:
The statement uses the adjective grueling to describe the race, which means very tiresome. It also adds that the race is over a thousand miles, which is a very great distance.
petulant means someone with bad manners or "an ill-mannered" person. Since the customer shouted and demanded to speak to a manager, this makes them petulant
