What grammatical role does a noun in the nominative case serve?

The nominative case is specifically used for nouns that function as the subject of a sentence. In grammatical terms, the subject is the part of the sentence that performs the action of the verb or is described by the verb. For example, in the sentence "The cat sleeps," "the cat" is a noun in the nominative case because it is the one carrying out the action of sleeping.

Understanding that the nominative case is reserved for subjects helps in recognizing how sentences are structured. In contrast, other roles such as objects of the verb or direct objects refer to different grammatical functions that do not align with the nominative case. Thus, when identifying nouns in the nominative case, it is essential to remember that they indicate who or what is engaged in the verb's action, reinforcing why the correct answer is the subject.