Let us find square root of each number one by one and see which one is not a perfect square.
A) 144
Square root of 144 is 12.
so it is a perfect square
B) 156
Square root of 156 is 12.5 which is not a whole number.
C) 169
Square root of 169 is 13.
So It is a perfect square.
D) 196
Square root of 196 is 14.
So it is a perfect square.
Answer is option B) 156 whose square root is not a whole number.
