As question states, the firewall is not in the traffic path. Tap is the interface that can receive traffic to identification.

The question stated "not in line of any DHCP traffic". For Vwire interfaces "Ensure the Virtual Wire is in the path for DHCP traffic. This traffic can be either broadcast or unicast." Tap interface use case "Monitor networks that don’t naturally traverse the firewall". D has to be the right answer.

A, sure

"Virtual Wire: When the firewall has Virtual Wire interfaces with multicast firewalling enabled, it generates Enhanced Application logs (EALs) for broadcast DHCP sessions." https://docs.paloaltonetworks.com/iot/iot-security-admin/get-started-with-iot-security/firewall-deployment-for-dhcp-visibility/firewall-deployment-options-for-iot-security

A. Virtual Wire: When the firewall has Virtual Wire interfaces with multicast firewalling enabled, it generates Enhanced Application logs (EALs) for broadcast DHCP sessions.

Vwire interface https://docs.paloaltonetworks.com/iot/iot-security-admin/get-started-with-iot-security/firewall-deployment-for-dhcp-visibility/firewall-deployment-options-for-iot-security