Northern Trail Outfitters (NTO) sends emails from Content Builder and Journey Builder.

Comprehensive and Detailed Explanation:

The correct answer is A — From the Reply Mail Management settings page, choose the "Create Custom Response" option under "Automated Response Email for Remaining Replies" section and select the HTML email.

RMM allows you to define an automated response for incoming replies.

You can specify a simple custom response and link it to a pre-built HTML email template through the RMM settings without requiring a triggered send setup.

❌ Why others are wrong:

B and C: Using a Triggered Send is more complex and usually unnecessary for a simple automatic response.

D: There’s no option to paste full HTML code into Admin > Account Settings for auto-replies — that's not how RMM is configured.

Exact Extract from Salesforce Official Documentation:

Salesforce Help — Reply Mail Management Setup:

"Configure a custom automated response by selecting 'Create Custom Response' under 'Automated Response Email for Remaining Replies' in Reply Mail Management. You can link a pre-built HTML email."

(Source: https://help.salesforce.com/s/articleView?id=sf.mc_es_reply_mail_management.htm )

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