Question:

When two words act as a single modifier, or adjective, for a noun, this is called a/an ________.
a. compound modifier
b. coordinating conjunction
c. adverb modifier
d. prepositional phrase

ANSWER:
a. compound modifier

Right!

What is a modifier?

A modifier is a word or group of words that describes or provides more detail about another word in a sentence. It can modify nouns, pronouns, verbs, adjectives or other adverbs. Modifiers can be single words or phrases and they can come before or after the word they modify. They can add information about time, place, manner, degree, and many other aspects of a sentence.

To determine the answer to this question, it is helpful to understand the terms involved.

A compound modifier is a combination of two or more words that together act as a single modifier for a noun. The two words work together to describe or modify the noun, and they usually appear together before the noun they are modifying.

To identify a compound modifier, look for two words that act as a unit and modify a noun together. For example, in the phrase "beautifully written book," "beautifully written" is a compound modifier because both words work together to describe the noun "book."

In the given options, 'a. compound modifier' is the correct answer that matches the definition described above.