Refer to the exhibit. If the two devices are operating normally, which two conclusions can you draw from this configuration? (Choose two.)

Question

Exhibit

Options

• ACE1 must use OSPF to establish a neighbor relationship with PE1.
• BPE1 labels the routes it learns from CE1 with the route-target 222:2 and shares them with its
• CPE1 labels the routes it learns from CE1 with the route-target 111:1 and shares them with its
• DThe PE-CE routes between the devices are being exchanged by OSPF
• ECE1 is supporting CSC.

• A
  79% (34)
• B
  7% (3)
• C
  12% (5)
• E
  2% (1)

Explanation

Options A and D are correct because they describe the same observable fact from two angles: the exhibit shows OSPF configured as the PE-CE routing protocol, which means CE1 must use OSPF to form a neighbor relationship with PE1 (A), and those routes are therefore being exchanged via OSPF (D).

Why the distractors fail:

• B and C both misidentify which route-target PE1 stamps on CE1-learned routes. In MPLS L3VPN, PE1 uses the VRF's export route-target to tag routes before advertising them via MP-BGP; only one of the two values shown can be the export RT, and the exhibit makes the other the import RT - so whichever value each option names, one must be wrong, and the phrasing (cut off at "shares them with its") also hints at an incomplete/misleading claim.
• E is wrong because CSC (Carrier Supporting Carrier) requires the CE to run MPLS/LDP and act as a mini-PE itself - a plain OSPF PE-CE adjacency is standard L3VPN, not CSC.

Memory tip: Pair A and D together as "same truth, two lenses" - the protocol (D = OSPF carries the routes) locks in the requirement (A = CE must speak OSPF). If you confirm one, the other is automatically correct.

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