Regarding choice B in Q1.
The key word in B is 'contrast'. This should there fore compare one thing with another. There is no sense of that in 'confusion and ambiguity' - it's more of a simple statement of fact about one city.
That this 'confusion and ambiguity' may only exist in one of the 2 cities is not enough - you're only looking at the highlighted text, and in that there is no 'contrast'
Former GMAT Pill student, now on staff. Used GMATPILL OG 12 and nothing else: 770 (48,48) & 6.0
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