Answer: D
In such question, we might take a look at the picture and see AB is bigger than OA and OB. ‌ Thus B is considered to be bigger.
The best way here is drawing a new circle which in that Angle AOB is too small then we will see that OA is bigger than AB and A is the answer. Also Ab can be equal to OA if all of the angles in the rectangle are 60 degrees, then C will be the answer.
So all of the options might be true and we can’t construe based on this shape without enough information.
The answer is D
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