Right answer is (d) \(\frac{1}{9}\)
The explanation: Let the radius of the balloon before pumping the air be “r”, then
A1 = 4πr^2
The radius of the balloon after pumping the air = 3r (given)
Hence, A2 = 4π(3r)^2
Therefore, \(\frac{A_1}{A_2} = \frac{4πr^2}{4π(3r)^2} = \frac{1}{9}\).