诊断慢性胃炎最可靠的依据是（）
A.慢性上腹部疼痛
B.胃酸常降低
C.X线钡餐检查
D.胃脱落细胞检查
E.胃镜检查及胃黏膜活检
参考答案：E
Could I speak to ______ is in charge of International Sales please?
A．who
B．what
C．whoever
D．whatever
