A sounds odd, Suresh. "zones" is plural while "it" is singular. Moreover, it is not clear what "it" refers to- is it the zones or is it the proposal? Ofcourse, WE know what "it" refers to. But the sentence given does not make it very clear.
A ) here "it" can refer to "proposal" or "principle" .. so it is ambigous
B --> one --represents proposal.
"proposal is not X but Y.. " Y -- proposal.
Is above reasoning correct?
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