汉代的买卖契约称为（）
A.质剂（西周的买卖契约）
B.傅别（西周的借贷契约）
C.券书
D.合同
参考答案：C
根据句意及首字母提示完成单词。
1. C______ is the biggest and the most important festival in the west on December 25.
2. The books are for the a ______. The children can't read them.
3. N______ the temperature of our body is 37℃.
4. She likes g______ better than apples.
5. People eat rice dumplings to r______ Qu Yuan.
卫星通信系统中较适用的扩频系统的基本类型有( )
A．2种
B．3种
C．4种
D．5种
