Four fair six-sided dice are rolled. What is the probability that at least three of the four dice show the same value? 
选项为:A:$\frac{1}{36}$  B:$\frac{7}{72}$  C:$\frac{1}{9}$  D:$\frac{5}{36}$  E:$\frac{1}{6}$  请回答其中一个选项.