The correct answers are B and C. In HPE Alletra 6000 / NimbleOS synchronous replication and Peer Persistence designs, the upstream and downstream volume relationship determines the active and standby host path behavior. HPE documentation states that when synchronous replication is configured, upstream and downstream volumes share the same serial number, and host paths are presented so that active paths are mapped to the upstream volume while standby paths are mapped to the downstream volume. That validates option B. Option C is also correct because in a bidirectional design, each array can host upstream volumes for some protected workloads and downstream volumes for others; the role is per replicated volume collection, not a permanent identity of the entire array. Options A and D are wrong because the witness is a separate arbitration component, not the upstream or downstream array. Option E is wrong because Alletra 6000 synchronous replication uses Ethernet connectivity between arrays, and Peer Persistence is not limited to FC-only host access. Reference/topics: HPE Alletra 6000 Peer Persistence, synchronous replication, upstream/downstream roles, witness design.