Which morpheme modifies a word's tense, number, or case?

The correct choice is indeed the inflectional morpheme, as it serves a specific grammatical function by modifying a word's tense, number, or case. Inflectional morphemes are suffixes added to the base form of a word without changing the core meaning of that word. For instance, in English, adding "-s" to a noun to indicate plurality (like "cat" becoming "cats") or adding "-ed" to a verb to indicate past tense (like "walk" becoming "walked") exemplifies this function.

Inflectional morphemes are crucial for conveying grammatical relationships and maintaining the syntactic structure of sentences. They provide essential information about how words relate to one another in terms of timing, quantity, and grammatical roles, thereby enabling clearer communication.

Other choices represent different types of morphemes that serve distinct purposes. Derivational morphemes, for example, can change a word's meaning or its part of speech, such as altering "happy" to "unhappy," which produces a different word entirely. Bound morphemes are those that cannot stand alone and need to be attached to another morpheme, while free morphemes can stand alone as words. These factors distinguish them from inf