【正确答案】 E

【答案解析】Rhetorical construction; Verb form
The relative pronoun which requires a clear antecedent, but none appears in the original version of the sentence. The company's announcement is entirely geared to the future—it will purchase the division as part of a deal that will make it the largest manufacturer.
A There is no antecedent for the relative pronoun which.
B Like a relative pronoun, the appositive phrase (apart...) must have a noun or noun phrase as a clear antecedent; the verb makes should be future tense.
C The appositive phrase requires a clear antecedent; making does not indicate future tense.
D This sentence is a little awkward (the article a in apart is unnecessary) and says something rather different; as a part of a deal to make suggests that the deal itself includes making the company the largest manufacturer rather than its being the outcome of the deal.
E Correct. The future tense is used throughout and the sentence structure is clear.
The correct answer is E.