When dealing with fully underlined sentences such as this, try to identify a single error first to streamline the elimination process for maximum efficiency. In the sentence as written, the pronoun "it" is ambiguous because it lacks a clear antecedent. Eliminate A and look for any choices that also include ambiguous pronouns. Choices B and C also include the ambiguous or otherwise erroneous pronouns "it" and "which" that do not correctly and clearly refer to a prior
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