请选择ABCD+g;Z/v/@7f5y*l.E,m-T4G7T The post office is a bit far from here. It's about_____.+W6I:C)F4P'r
A. thirty minutes's walk+W6I:C)F4P'r
B. thirty minute's walk+W6I:C)F4P'r
C. thirty minutes' walk+W6I:C)F4P'r
D. thirty minutes walk+W6I:C)F4P'r