组件图展现了一组组件之间的组件和依赖。它专注于系统的（）实现图。
A、动态
B、静态
C、基础
D、实体
参考答案：B
In addition to keeping on taking ________ exercise, Alan is also going on ____ diet to lose weight.
A．an; a
B．an; /
C．/; /
D．/; a
种子经营者的义务有哪些？
