Which PAN-OS method of mapping users to IP addresses is the most reliable?

A network engineer observes a pattern of anomalous traffic hitting an external-facing zone, including a high volume of TCP packets that are not part of a new session handshake (non-SYN), and a large number of ICMP fragments. The engineer decides to apply a Zone Protection profile to mitigate these potential threats.
Which protection type within the profile must be configured?

A network administrator is configuring an Aggregate Ethernet (AE) interface on an active/passive high availability (HA) pair. To reduce network downtime during a failover, the administrator wants the passive firewall's AE interface to be fully negotiated with the switch before it becomes active.
Which Link Aggregation Control Protocol (LACP) setting achieves this administrator's goal?

An NGFW is deployed inline to inspect traffic without requiring any changes to existing IP addressing or routing configurations.
Which deployment mode is being used?

An administrator enables SSL Forward Proxy decryption using a self-signed certificate on a Palo Alto Networks firewall as the forward trust certificate. Shortly after, users report receiving "Your connection is not private" browser errors for all external websites.
What is the most likely cause of these widespread certificate errors?