汇款结算方式，对于（）而言，风险较大，有可能钱货两空。
A.预付货款的买方
B.预付货款的卖方
C.货到付款的卖方
D.货到付款的买方
参考答案：A, C
Mr. Black is strongly _______keeping animals in the zoo, because he thinks animals should also have the right to enjoy freedom.
A．up
B．for
C．against
D．down
植物病原原核生物有哪些特征？主要包括哪些类型？
