When configuring a sending domain for SAP (Sender Authentication Package), you need to know:

If the company allows delegation of subdomains to a third party (Marketing Cloud).

Whether they can modify the DNS entries (important for setting up SPF, DKIM, and CNAME records).

Options A and C incorrectly imply that Salesforce/Marketing Cloud will update or post files directly, but typically, DNS configuration must be done by the customer’s IT team.

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Exact Extracts from Salesforce Documentation:

Source: Salesforce Help – Domain Delegation for Marketing Cloud

→ "Delegation of subdomains to Salesforce is often required if Marketing Cloud is to manage the domain authentication setup."

Source: Salesforce Help – Sender Authentication Package DNS Requirements

→ "Customers must be able to add and manage DNS records, including TXT, CNAME, and MX records, to complete the domain branding process."