问答题 Drag and drop question. The upper gives the MPLS functions， the bottom describes the planes. Drag the above items to the proper location at the below

单项选择题 Study the exhibit carefully. Routers A and B are customer routers. Routers 1， 2， 3 and 4 are provider routers. The routers areoperating with various IOS versions. Which frame mode MPLS configuration statement is true？（）

单项选择题 A new router was configured with the following commands： The configuration above was found on an Internet Service Provider’s （ISP） Multiprotocol LabelSwitching （MPLS） network. What is its purpose？（）