The correct response is: "Due to their status as antonyms, 'listless' likely means 'lacking energy.'"
The term "rowdy" indicates a lively, energetic behavior often associated with noise and excitement, while "listless" describes a lack of energy or enthusiasm. The contrast between the two terms helps the reader understand that after a month of the challenging journey, the individuals have lost their initial vigor and become indifferent or lethargic.