The word "remains" is the correct answer because it is the only word that fits the context of the given words "debris," "clean," and "debts." "Remains" can refer to leftover or remaining parts of something, which is related to debris. It can also be used to describe what is left after cleaning or clearing something, which connects to the word "clean." Lastly, "remains" can also refer to unpaid debts or obligations, which relates to the word "debts." Therefore, "remains" is the most suitable word among the given options.