Their mother ________ dinner at the kitchen when a quarrel ________ among the children.[ ]

A. was preparing; was broken out

B. prepared; was broken out

C. was preparing; broke out

D. prepared; broke out

集体经济是由部分劳动者共同占有生产资料的主要经济形式，它可以

A．体现共同富裕的原则

B．广泛吸收社会资金，缓解就业压力

C．以劳动者自己的劳动为基础

D．控制国民经济的命脉