Final answer:
In the given sentence, 'clear' is functioning as an adjective, which is a word that describes or modifies other words.
Step-by-step explanation:
In the provided sentence, the word 'clear' is functioning as an adjective. Adjectives are words that describe or modify other words in a sentence. In this scenario, 'clear' is used to describe the manner in which the response should answer the student's question. Hence the correct answer is A) Adjective.
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