Answer:
C. A word that refers to an idea, a quality, or an action
Explanation:
A noun is a word that denotes the name of any object, feeling or thing. An abstract noun is a type of noun. It represents the abstract things that can be felt and not touched or seen. It represent an idea or the quality. Intangible things are denoted by the term abstract noun. For instance, death, friendship, anger and beauty are some of the examples of Abstract noun. These words cannot be touched or seen but they can be felt.