Athrift store is a good place to find unique clothing. in the sentence, the infinitive phrase to find unique clothing functions as a. an adverb. b. an adjective. c. a noun. d. a verb.

B. Adjective

Explanation:

i just did this question on Study Island

sufficient and relevant

explanation:

quite an interesting way to teach topic sentences, because the answer to this question is the best definition of a topic sentence that one can present, it is as if answering the questions taught you how to do it, this is some real teaching, it is terribly well-done.

the topic sentence in this paragraph is:

topic sentences writers stay on track and keep a paragraph from becoming an aimless collection of sentences about an idea.

which incidentally tells you what a topic sentence should be.