Final answer:
The correct revision for sentence 4 is option A: It was such a big deal they had special cups for it.
Step-by-step explanation:
The correct revision for sentence 4 would be option A. It was such a big deal they had special cups for it. This revision maintains the formal tone of the previous sentences and accurately conveys that the Aztecs and Mayas regarded the chocolate drink as something important and significant.
Learn more about Sentence revision for tone