阵发性房颤：症状明显、室率快，首选治疗是（）。
A.口服胺碘酮
B.静脉注射西地兰
C.同步直流电复律
D.暂不予治疗
E.奎尼丁转复
参考答案：B
Wang Gang is considering buying a computer, _____ is considered to be a great help in our work and study. [ ]
A. as
B. which
C. that
D. what
隧道式巴氏杀菌机的操作工可不戴防爆面具。
