correct answer is : d) 2

Explanation

Here, we have = \frac{9}{50}
\rightarrow If we do the prime factorization of numerator and denominator, we get :
\rightarrow\ \frac{9}{50}\ =\ \frac{3\ \times\ 3}{2\ \times\ 5\ \times\ 5}\ =\ \frac{3^2}{2\ \times\ 5^2}
\rightarrow since, the factor of denominator are not in pair.
\rightarrow here, \frac{9}{50} is not a perfect square fraction.
\rightarrow therefore, to make \frac{9}{50} a perfect square fraction, it must be multiplied by the positive integer ‘2’.
Ans: The least positive integer is ‘2’.