The DNS record that defines the mail routing information for a domain is:

The DNS record that defines the mail routing information for a domain is:

• A. A
• B. NS
• C. SRV
• D. MX

Answer: (D)

Mail delivery for a domain is guided by the Mail Exchange (MX) record. This DNS type specifies which host is responsible for receiving email for the domain and can assign a priority to that host. When another mail server wants to deliver mail to the domain, it queries DNS for MX records, tries the highest-priority entry first, and, if that host is unavailable, proceeds to the next one. The MX target is a hostname, which should have its own A/AAAA record to map to an IP address. This is distinct from A records, which map a hostname to an IP, NS records, which indicate the domain’s authoritative name servers, and SRV records, which locate specific services for protocols. So, the DNS record that defines mail routing information is the MX record.

Mail delivery for a domain is guided by the Mail Exchange (MX) record. This DNS type specifies which host is responsible for receiving email for the domain and can assign a priority to that host. When another mail server wants to deliver mail to the domain, it queries DNS for MX records, tries the highest-priority entry first, and, if that host is unavailable, proceeds to the next one. The MX target is a hostname, which should have its own A/AAAA record to map to an IP address.

This is distinct from A records, which map a hostname to an IP, NS records, which indicate the domain’s authoritative name servers, and SRV records, which locate specific services for protocols. So, the DNS record that defines mail routing information is the MX record.