The League Secretary and monitor ______giving a speech while the rest of the class ________ listening attentively.

A．were, were

B．was, was

C．were, was

D．was, were

采标标志由（）采用，并对使用采标标志的产品质量承担法律责任。

A.企业自愿

B.国家强制

C.国家鼓励

D.国家推荐