In the network shown in the figure, OSPF 100 runs on RTA, RTB and RTC, and RTA and RTB establish EBGP neighbor relationship with RTD respectively.

AS 200 advertises the route 10.10.10.0/24 to AS 100, and sets the MED value of the route advertised to RTA to 100, and the MED value of the route advertised to RTB to 200.
The main configurations of RTA and RTB are as follows:
RTA]
bgp 100
peerRTD as-number 200
peerRTB as-number 100
ospf 100
import-route bgp cost 10
RTB]
bgp 100
peerRTD as-number 200
peerRTA as-number 100
ospf 100
import-route bgp cost 20
Users expect RTC to choose RTA when accessing 10.10.10.0/24, but it turns out that RTC chooses RTB for data forwarding.
How should appeals be resolved?

In the regular expression, all routes are _____________.

As shown in the figure, the router interface is configured with the IPv6 link-local address FE80::2009:1, and advertises the prefix 2009:10:121::/64 on the link, then the gateway address obtained by the node on the link is _______.

The networking is as shown in the figure, RTA and RTB are located in AS 100, RTC, RTD, RTE are located in AS 200, AS 100 advertises BGP route 1.0.0.0/24 to AS 200, the main configuration of BGP of RTC and RTD is as follows, if RTE, RTD The interconnect link is interrupted, RTE accesses the 1.0.0.0/24 network segment, which WAN link is preferred?

In an OSI network, Level-0 routing exists in _______.