Which is the likely source of the issue?

After filtering a fw monitor trace by port and IP, a packet is displayed three times; in the "I", "I", and ‘o’ inspection points, but not in the ‘O’ inspection. Which is the likely source of the issue?

A.
The packet has been sent out through a VPN tunnel unencrypted.

B.
An IPSO ACL has blocked the outbound passage of the packet.

C.
A SmartDefense module has blocked the packet

D.
It is an issue with NAT