The sum of the digits of a 3 digit number is subtracted from the number,the resulting number is always:-

1. Divisible by 6
2. Divisible by 9
3. Not divisible by 6
4. Not divisible by 9

Let, any random three digit number say 568, its digits sum is 19.

Now, on subtracting 19 from 568, we get 549 which is divisible by 9.

Hence, the resultant number after subtracting sum of three digits form the the number will always be divisible by 9.
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