新开业的纳税人自税务登记日起（）日内可以申请一般纳税人资格认定。
A.15
B.20
C.30
D.40
参考答案：C
患儿4岁，曾多次患肺炎，平时无发绀，活动后气促。体格瘦小，心前区隆起，胸骨左缘第2肋间闻3级连续性杂音，伴有水冲脉。最可能的医疗诊断为（）
A.房间隔缺损
B.室间隔缺损
C.法洛四联症
D.动脉导管未闭
E.肺动脉瓣狭窄
People living in the area where there is a lack of electricity often keep a supply of candles ________power failure.
A．in case of
B．once
C．even if
D．in course of
