The Diaoyu islands have been part of China's territory since ancient times, ________ as important fishing grounds of Taiwan.

A．served

B．to serve

C．serving

D．having served

五岁患儿，平时不发绀，曾多次患肺炎并发心力衰竭。

提示：胸骨左缘第2肋间可闻及心脏杂音提问：该患儿可能的诊断为()

A.室间隔缺损

B.房间隔缺损

C.法洛四联症

D.动脉导管未闭

E.肺动脉狭窄

F.大动脉转位