The smallest whole number that is to be multiplied with 59535 to make a perfect square number is x. The sum of digits of that number is?

Answer: Option A

$$59535=3\times 5\times \boxed{3\times 3}\times \boxed{3\times 3}\times 7\times 7$$
⇒ To make a perfect square we should multiply by = 3 × 5 = 15
x = 15 [given]
⇒ Sum of digits of number = 1 + 5 = 6