下列关于F1力臂的作图中，正确的是[ ]
A.
B.
C.
D.
答案：C
H3C远程灾备解决方案中采用的复制技术是基于哪些层次的复制技术？（）
A.网络
B.应用
C.主机
D.磁盘阵列
Usually there might be a lot of accidents in the heavy fog. I happened to witness ______ this morning. [ ]
A. it
B. those
C. one
D. that
