The Sino-USA agreement on trade relation, which came into force in Feb.1980, accords China most favoured nation treatment．( )
A、came to
B、came into being
C、signed
D、took effect
【正确答案】：D
【题目解析】：came into force意为”生效“；came to来到；came into being出现，形成；signed署名，写下；took effect生效；故选D。
