GMAT Critical Reasoning (CR) | Re: All of John's friends say they know

IMO, since John is NOT UNIQUE ->he is the same with SOME or MOST of his friends (say another way, he is the same at least ONE of his friends)
Let take an example set of 100 John's friends:
SOME has wider range of possibilities (1-100), and MOST (51-100) is a subset of SOME
So, E is a Must be True

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