Which of the following represents an example of an inflectional morpheme?

An inflectional morpheme is a type of morpheme that modifies a word's tense, number, aspect, or case without changing its grammatical category. In this context, the suffix "-s" is an inflectional morpheme because it often indicates the plural form of nouns (e.g., "cat" becomes "cats") or can denote the third-person singular form of verbs in the present tense (e.g., "he runs"). This type of morpheme alters the form of the word to convey additional grammatical information while keeping the word within the same grammatical class.

The other options reflect derivational morphemes, which change the meaning or grammatical category of a word rather than just providing grammatical information. For example, "-ing" denotes the gerund or participle form of verbs, "-ly" transforms adjectives into adverbs, and "-ness" converts adjectives into nouns. Each of these examples represents a change in meaning or function, which distinguishes them from the inflectional nature of "-s."