Exam 300-710 topic 1 question 252 discussion

C is most correct, but not entirely. The FTD in transparent mode will allow DHCP requests and responses to pass between the workstations and the DHCP server without interference, as long as no policies explicitly block UDP ports 67 and 68.

For example, by using an access rule, you can allow DHCP traffic (instead of the unsupported DHCP relay feature) or multicast traffic such as that created by IP/TV. You can also establish routing protocol adjacencies through a transparent firewall; you can allow OSPF, RIP, EIGRP, or BGP traffic through based on an access rule. Likewise, protocols like HSRP or VRRP can pass through the FTD device. https://www.cisco.com/c/en/us/td/docs/security/firepower/670/configuration/guide/fpmc-config-guide-v67/transparent_or_routed_firewall_mode_for_firepower_threat_defense.html

I would go for C since it will inspect the traffic within the same subnet, so being transparent is required.