某儿童8岁，爱探究、好攻击、喜欢表现自我，这是人生发展的()。

A．被动发展阶段

B．主动发展阶段

C．自主发展阶段

D．巩固发展阶段

E．晚年发展阶段

— How long has the nationwide ban (禁止) on plastic bags been put into practice? 

—             the beginning of June. [ ]

A. Behind

B. Since

C. For

D. At