地球上最基本的生命系统是[ ]
A．生态系统
B．群落
C．种群
D．细胞
答案：D
Could I speak to ________ is in charge of International Sales, please? [ ]
A. anyone
B. someone
C. whoever
D. no matter who
治疗肾虚骨痿，囟门不合，宜首选
A．女贞子B．枸杞子C．龟甲D．鳖甲
