补全对话，从所给选项中选择一个填入横线上。
Mr. Green: Morning, Mr. Wu! You’re walking today. Do you usually come to school by bike (骑自行车) ?
Mr. Wu:  1   . But I sometimes walk.     2 .
Mr. Green: Walking is good. Look at the sun. 3 __.
Mr. Wu:   4  _ . And the air today is nice and clean. Do you come to school by bike?
Mr. Green:   5    .
Mr. Wu: Why not?
Mr. Green: Because my bike is broken.(坏了).
Mr. Wu: Broken? Oh, I see!

A．It’s a fine day for walking today.

B．Yes, but not today.

C．Yes, I do.

D．That’s right.

E. I like walking.