— I heard that you would study abroad next term.

— ____. We can keep in touch with each other by E-mail. [ ]

A. So do I

B. Nor do I

C. So will I

D. So I will

小明要在一个长50米，宽30米的长方形操场旁边种树，每隔10米种1棵，并且四个角都种树。一共可以种( )棵树。

A．14
B．15
C．16
D．17