Refer to the exhibit. All routers are configured for BGP. EBGP routes received on router R2 showup in the BGP table on routers R1 and R3 but not in their IP routing tables. What would causethis？（）

• A、EBGP multihop is not configured on routers R1 and R3
• B、Routers R1 and R3 do not receive the same routes via an IGP
• C、Synchronization in autonomous system 100 is turned is on
• D、The BGP routers in autonomous system 100 are not logically fully-meshed
• E、Synchronization in autonomous system 100 is turned is off