下列不易造成局限性肺气肿的是（）
A.支气管异物
B.支气管扩张
C.支气管囊肿
D.支气管良性肿瘤
E.支气管恶性肿瘤
参考答案：C
Two techniques for forecasting cash flows are to use projection models and averages, or statistical techniques. Which of these two methods would be most appropriate for: medium-term forecastinglong-term forecasting（）
A. Statistical techniques Statistical techniques
B. Statistical techniques Projection models and averages
C. Projection models and averages Statistical techniques
控制保洁质量的最常用的方法是（）。
A.自查
B.经常检查
C.定期查
D.抽查
