A customer has curated a list of known email addresses belonging to competitors.

✅ Comprehensive and Detailed Explanation: An Auto-Suppression List is specifically designed to automatically exclude specific email addresses or Subscriber Keys from being sent emails in Marketing Cloud. In this case, since the list of competitors' email addresses is static and curated, populating an Auto-Suppression List with these known addresses ensures that no emails are sent to them without requiring manual intervention.

❌ Why Other Options Are Incorrect:

A: Using Subscriber Keys would require guaranteed mapping, but email address is the direct data available here.

B: Queries require manual maintenance and are not an automatic suppression mechanism.

C: Exclusion Lists typically apply to one send definition or journey; Auto-Suppression Lists apply globally across all sends.

Exact Extract: Salesforce Help: Auto-Suppression Lists

"An auto-suppression list prevents email sends to specific subscribers globally, based on Subscriber Key or Email Address."

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