The circle with radius \(\frac{4}{\sqrt{n}}\) is equal to the area of a square.

Use the circle area formula

\(A = \pi ( \frac{4}{\sqrt{n}}) ^2\)

A = 16

Hence the area of the square is 16 and a single side is 4.

Now QB says if the side is increased by one. Therefore, one side is 5. From this the area is 25.

But QA is \(9 \pi\) that is more than 27 ( 9 * 3.14).

The answer is A

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