—Mom, can I leave my homework for tomorrow?

—I’m afraid not. Don’t           what you can do today till tomorrow.[ ]

A. put on      

B. put off        

C. put down      

D. put up

岛弧亚型大陆边缘主要分布在西太平洋，组成单元缺失大陆隆，发育结构为（）体系。