We were shocked to hear the news that ________ two Chinese engineers were shot to death in Pakistan. Worse still, ________ third one died in hospital afterwards.

A．/; a

B．the; the

C．the; a

D．/; the

同类组合是在保持事物原有（）或原有意义的前提下，通过数量的增加以弥补功能上的不足或求取新的功能。