When number $\overline{OK}$ is divided by $K$, the result will give the same quotient as the divisor and leave the remainder of $O$. The same letter represents the same digit, and different letters represent different digits. Then, what is the product of the two digits, $O$ and $K$? 
选项为:A:$$18$$  B:$$36$$  C:$$63$$  D:$$72$$  E:$$81$$  请回答其中一个选项.