确诊溃疡活动性出血的最可靠的方法是（）
A.胃液分析
B.X线钡餐检查
C.大便隐血
D.急诊胃镜检查
E.血色素测定
参考答案：D
人工床层
for the free tickets,I would not have gone to the film so often.
A．If it is not
B．Were it not
C．Had it not been
D．If they were not
