核苷中碱基与戊糖的连接方式（）
A.肽键
B.磷酸二酯键
C.磷酸酯键
D.酯键
E.糖苷键
参考答案：E
_______ natural resources it is one of the poorest countries in Europe.
A．In the eyes of
B．In honor of
C．At the mercy of
D．In terms of
简述光伏发电站的组成及原理。
