Exam 300-410 topic 1 question 89 discussion

I think the answer is B and C. D should be MPBGP. According to this document: Segment routing is a method of forwarding packets on the network based on the source routing paradigm. Segment routing leverages other Interior Gateway Protocols such as IS-IS, OSPF, and MPLS for efficient and flexible forwarding. Segment routing is a faster and a more efficient way of forwarding traffic in the MPLS core network.A router in aSegment Routing network can select either an explicit path or a default Interior GatewayProtocol (IGP) shortest path. Segments represent subpaths that a router can combine to form a complete route to a network destination. Each segment has an identifier (Segment Identifier) that is distributed throughout the network using new IGP extensions. Each router (node) and each link (adjacency) has an associated segment identifier (SID). Node segment identifiers are globally unique and represent the shortest path to a router as determined by the IGP.