The last option (7,695) is the only option that is perfectly divisible from 9.
All the others options divided by 9 would leave you with an imperfect number with decimal points. However, when you divide 9 from 7,695, you get a perfect whole number.
A function cannot be a function if any x is repeating. The x in A has the number 1 repeating. The x is C has 2 repeating the x in D has 1 repeating. Therefore, our answer would be (B)
