Explain what a suppression list is and how to use it.

• A. A list of emails that are frequently bounced in the past quarter.
• B. A list of addresses from a previous campaign that performed exceptionally well.
• C. A list of non-subscribers who requested removal but were not unsubscribed.
• D. A list of addresses you should not mail (unsubscribed or bounced); used to prevent unwanted sends.

Answer: (D)

A suppression list is a safety gate for email sends. It’s a maintained list of addresses you should not mail because the recipient has opted out or because previous mail to that address bounced, failed, or caused complaints. Before sending a campaign, you exclude any addresses on this list from your recipient set, so you don’t waste sends or harm your sender reputation. This practice helps you honor unsubscribe requests, reduces spam complaints, and improves deliverability over time. In practice, the suppression list covers unsubscribes and bounced addresses, which is why describing it as a list of addresses you should not mail (unsubscribed or bounced) to prevent unwanted sends is the most accurate summary. Other options mention related ideas—like bounced addresses alone or engagement data—but those don’t fully capture the protective, opt-out–honoring function of a suppression list.