The two boys_____ games on the computer for three hours, and they would continue till midnight

A．were playing

B．had played

C．had been playing

D．has been chatting

下图是毛 * * 会见田中角荣时的情景。这一现象出现的直接促进因素是

A．中国国际地位提高

B．中美两国正式建交

C．中美两国关系缓和

D．新中国重返联合国