D. He told my brother that some great deals can be found at the flea market.
Explanation:
In this sentence, the antecedent is missing. When we use a pronoun, we are substituting a noun. This noun is the antecedent of the pronoun, or the word the pronoun refers to. In this case, the author tells us that "he" told the brother something. However, "he" is a pronoun, and the sentence does not indicate who this pronoun refers to.
