单选题 Communication networks can be classified in terms of their physical arrangement or (74) Three common (74) are the star, bus, and ting.

【正确答案】 B
【答案解析】[分析] 信息网络可以依据物理结构或拓扑结构进行分类，3个典型的拓扑结构是星形、总线型和环形。