The parents didn't tolerate their kids' rudeness at the party, nor ______ themselves to be disobeyed.

A．they allowed

B．did they allow

C．didn't they allow

D．they didn't allow

厂商不是根据不同的消费者而是根据不同的购买数量或购买时间来确定价格的属于（）.

A.一级价格歧视

B.三级价格歧视

C.二级价格歧视

D.完全价格歧视