对放射线敏感的肿瘤是 （）
A.恶性黑色素瘤
B.颌骨肉瘤
C.脂肪肉瘤
D.颌下腺腺癌
E.以上都不是
参考答案：E
There is no ______ swimming-pool in this school and the students often go to swim ______. [ ]
A. indoors; outdoors
B. indoor; outdoor
C. indoor; outdoors
D. indoor; indoors
描述暴露与疾病关联强度的指标是（）。
A．发病率
B．患病率
C．相对危险度
D．以上均是
E．以上均不是
