What could be the reason the customer received the email through MCC?

Northern Trail Outfitters received a complaint today from a customer who received an email after unsubscribing last week. Today’s email was sent using Marketing Cloud Connect (MCC), though last week was sent when an external system dropped a file on the Marketing Cloud SFTP and triggered a User-Initiated Send through an automation.

What could be the reason the customer received the email through MCC?
A . The previous send’s user needed to have edit permissions in Salesforce,
B . Email Opt Out is only updated if the send originates in Salesforce.
C . The previous send used Email Address as a Subscriber Key.
D . The Email Opt Out field needs to be added to the Contact Page Layout.

View Answer

Answer: C