我国急性胰腺炎的最常见病因为
A．胆道疾病
B．手术创伤
C．高钙血症
D．并发于流行性腮腺炎
E．大量饮酒和暴饮暴食
参考答案：A
He's got himself into a dangerous situation ___he is likely to lose control over the plane.[ ]
A. where
B. which
C. while
D. why
