下述哪支动脉不起源于肠系膜上动脉
A．结肠中动脉
B．胰十二指肠上动脉
C．回结肠动脉
D．胰十二指肠下动脉
E．结肠右动脉
参考答案：B
任意性规范
—What happened in Indonesia?
—________ December, 2004, a strong earthquake hit Indonesia and the big tsunamis (海啸) followed. [ ]
A. On
B. At
C. By
D. In
