The FortiManager 7.6 Administrator Study Guide is explicit for the scenario where both FortiManager and FortiGate are behind NAT. It states that FortiManager can discover FortiGate through the FortiGate NATed IP address, which makes A correct. It also explains that in this scenario, the FortiManager NATed IP address is not configured on FortiGate by default under central management, which makes B correct.

C is incorrect because FortiGate must use the FortiManager NATed IP address, not the non-NATed IP, if it needs to announce itself or reestablish the FGFM tunnel. D is also incorrect because in this NAT scenario, if the tunnel is torn down, only FortiGate attempts to reestablish the connection; FortiManager does not automatically do so.

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