The correct answer is <u>A</u>: Chelsea felt tired during the race because she grew warm from the sun.
Explanation:
Chelsea didn't run faster or further than Brian did. In fact, Brian was faster and he ran further than Chelsea, but he suddenly fell and injured his knee. However, she decided to stop down and help him stand.
At the beginning of the excerpt, the author describes the race and says the sun was warm, so she soon grew tired because of the sun, but she decided not to quit the race.
