Final answer:
The best clue to the theme of unexpected courage is the sentence that emphasizes Jaime being the smallest and youngest but still willing to take on the challenge. option D is the correct answer.
Step-by-step explanation:
The sentence from the passage that provides the best clue that a theme of the story is "Courage can be found in the people you least expect it" is "He was the smallest and youngest of the group, barely strong enough to carry his large backpack."
This sentence highlights the unexpected nature of Jaime's courage, suggesting that despite his physical appearance, which might not typically be associated with strength, he possesses a brave heart and is willing to face the challenge of retrieving the lost ice samples.
This demonstrates a form of courage that might not be expected from someone who seems physically weaker than the others.the others.