$\begin{array}{1 1}(A)\;\large\frac{9990C_2}{10000C_2}\\(B)\;\large\frac{9980C_2}{10000C_2}\\(C)\;\large\frac{9970C_2}{10,000C_2}\\(D)\;\large\frac{9000C_2}{10,000C_2}\end{array} $