Dynamic reply addresses require an authorized email domain , which is different from an authenticated sending domain. After the consultant adds the domain under Unified Messaging → Authorized Email Domains, Salesforce generates a verification code. The administrator must add that value to the organization's DNS as a TXT record , then return to Salesforce and verify the domain.

Salesforce uses this verification to establish domain ownership before Marketing Cloud Next allows dynamic reply-to addresses on that domain. If a dynamically resolved reply address uses an unauthorized domain, Marketing Cloud Next falls back to the configured fallback reply address. Salesforce reiterated this behavior in an August 28, 2026 support article.

An Authenticated From Address pertains to outbound email sending rather than authorizing dynamic replies. Sender Authentication Package is associated with other Marketing Cloud architectures and isn't the next step in Marketing Cloud Next's Authorized Email Domains workflow.

The master file correctly identifies C.

Study Guide Reference: Platform Setup and Governance → Unified Messaging → Authorized Email Domains and Dynamic Reply Addresses.

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