Find the odd one out 

204, 315, 425, 531, 624

Sum of digits of 204 = 2 + 0 + 4 = 6

Sum of digits of 315 = 3 + 1 + 5 = 9

Sum of digits of 425 = 4 + 2 + 5 = 11

Sum of digits of 531 = 5 + 3 + 1 = 9

Sum of digits of 624 = 6 + 2 + 4 = 12

Sum of digits of 204, 315, 531, 624 is divisible by 3 so 204, 315, 531, 624 are divisible by 3.

Sum of digits of 425 is not divisible by 3 so 425 is not divisible by 3.

$$\therefore\ $$425 is the odd one among the given numbers.

Hence, the correct answer is Option C