Final answer:
An adjective is a word that describes or modifies a noun or pronoun. In this case, 'nervous' is the adjective that describes the noun 'nerve'.
Step-by-step explanation:
An adjective is a word that describes or modifies a noun or pronoun. It provides more information about the noun or pronoun. In this case, the word 'nervous' is an adjective because it describes the noun 'nerve'. The adjective 'nervous' tells us more about the type or state of the nerve. The other options, 'onerves', 'nerve', and 'lily', are not adjectives as they do not modify or describe a noun or pronoun.
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