How Does Symantec DLP Communicate with Symantec Messaging Gateway (SMG)

How does Symantec DLP communicate with Symantec Messaging Gateway (SMG) to indicate what type of incident (if any) is related to a given message?

A) Symantec DLP uses the ICAP protocol to indicate if a message is clean, or if it violated any defined policies.
B) Symantec DLP will add information into the message that can be interpreted by SMG and then send it to SMG via SMTP.
C) Symantec DLP will quarantine messages that violate established policies, blocking it from SMG.
D) Symantec DLP will use TLS to send a notification message to the SMG server for any content violations.