10. Among the four-digit integers from $1000 \sim 9999$, there are ( ) numbers whose digits are all different.
(A) 3024
(B) 4536
(C) 5040
(D) 6480
(E) 6261
$\begin{array}{l}\text { 10. B. } \\ 9 \times 9 \times 8 \times 7=4536 \text {. }\end{array}$