(7 - 84) , (6 - 108) , (5 - 75) , (3 - 99)
Option:
Justification: In all other pairs, the second number is obtained by multiplying the square of the first number by a prime number. Thus, 108 = 6² × 3, 75 = 5² × 3, 99 = 3² × 11.

(7 - 84) , (6 - 108) , (5 - 75) , (3 - 99)
Justification: In all other pairs, the second number is obtained by multiplying the square of the first number by a prime number. Thus, 108 = 6² × 3, 75 = 5² × 3, 99 = 3² × 11.