The BEST response that completes the R.A.C.E strategy for the prompt about using modifiers correctly is:
"It is important to use modifiers so that the right words are used and that readers understand what is happening in the sentence. They are words, phrases, or clauses that describe. Be careful when using modifiers in your own writing."
This response effectively restates the prompt, provides a clear answer about the importance of modifiers, cites evidence by defining what modifiers are, and explains the evidence by emphasizing reader understanding and caution in usage.