保兑行承担的是（）的信用风险。
A.进口商
B.出口商
C.开证行
D.议付行
参考答案：C
If you want to talk to your teacher,you should _____ first.[ ]
A. called to her
B. called up her
C. call her up
D. called her up
组成脾白髓的结构是（）
A.淋巴小结、中央动脉和动脉周围淋巴鞘
B.脾索和脾窦
C.淋巴小结和脾窦
D.淋巴小结和脾索
E.边缘区和脾小梁
