GMAT Critical Reasoning (CR) | Re: Utility companies in the United States are generally private

I picked A and here is my 2 cents.

First, this one asks about“supporter assumption ”.
The form of this question islike:
X is not Y
Because of A, X should be Y
The assumption is: A requires X to be Y.

For example:
In the past, almost CEOs in company X did not hold anMBA
Because of the new hiring rules , all CEOs in company X should hold an MBA.
==>Assumption: new hiring rules require all CEOs applicants to hold an MBA.
If wenegate this assumption: new hiring rules require all CEOs
...

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