单项选择题
A.monitor start test
B.show log test
C.view log test
D.show test realtime
多项选择题 Which three SONET network elements are used for troubleshooting?（）
单项选择题 When troubleshooting ATM, which command would allow you to test reachability from one side of an ATM cloud to the other?（）
单项选择题 Which command would you type to see a concise display of which interfaces are up and which are down?（）