Since this is a select one multiple choice ans there cannot be more than

1 ans choice. If in the process of solving the problem we get our ans, no need to work with other options.

There can be other methods for solving the ans for eg. you can formulate a eqn \(x(x-1) = 2a\); where a is the ans options

make the left side equivalent to the right side for correct ans such as \(x(x-1) = 4*3\) for option B try it with different options only B is correct

Realize that this is not a time consuming question. If you understand the logic the question should not take more than 1'30 min to answer

Wording of questions can be confusing, ets regularly uses this technique to make test-takers chose wrong answers. Get familiar with gre language. Give attention to sign words such as only, not, must be, could be, if, approximately and so on

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This is my response to the question and may be incorrect. Feel free to rectify any mistakes

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