Which three statements about the Cisco MPLS TE Fast Reroute （FRR） process are true？（）

• A、TE tunnels that are configured with the FRR option cannot be used as backup tunnels.
• B、TE tunnels that are configured with the FRR option can be used as backup tunnels.
• C、The backup tunnel that is used to protect a physical interface must have a valid IP address configured.
• D、Interfaces must use MPLS global label allocation.
• E、The source IP address of use backup tunnel and the merge point （MP） should not be reachable.