Sentence Correction (SC) | Re: The financial crash of October 1987 demonstrated that the

1. Firstly, the idiom is "More X than Y"- which therefore is also a parellelism marker. The X should be parallel to the Y.
2. Secondly, look at the meaning. The author means to say that it was closely integrated before but it is even more so now. Hence B because it conveys that PRECISE meaning, which D does not.

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