99色精品-9色在线-99色在线-99色视频 国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項選擇題

Which of the following denotes the FINAL point of responsibility for a service provider?()

A. 66 block
B. Patch panel
C. Wiring closet
D. Demarc

微信掃碼免費搜題