The second number in the given number-pairs is obtained by performing certain mathematical operation(s) on the first number. The same operation(s) is/are followed in all the number-pairs, except one. Find that odd number-pair.

(NOTE: The relation should be found without breaking down the numbers into its constituent digits)

A

225 : 169

B

361 : 400

C

529 : 576

D

441 : 484