—Which of the two subjects do you like, art or music?

—        . They are really interesting.

A．Neither

B．Both

C．None

D．All

高速公路路堤施工中，横坡陡峻地段的半填半挖路基，必须在山坡上从填方坡脚向上挖成向内倾斜的台阶，台阶宽度不应小于( )。

A．1m

B．2m

C．3m

D．4m