I don't think it's C here. The dedicated stateful link (B) actually syncs active sessions between chassis for seamless user experience. C is about software version compliance, but that alone won't keep connections alive on failover. B is the one to go for in this scenario.

Had something like this in a mock and B was right. The dedicated stateful link is what keeps session info synced so users don't lose connections during failover. Pretty sure that's the only way to really keep it seamless for end users. Someone let me know if you think otherwise.

B

I see C and B both make sense because software versions do matter, but for truly seamless failover users only notice, official labs and Cisco's Firepower config guide both highlight that you need the dedicated stateful link (B). Anyone double-checked with the latest practice tests? I might be mixing up ASA/Firepower details.