To validate the authenticity of email senders, which type of DNS record is primarily used to specify authorized mail servers for a domain?

Correct option is D

The SPF (Sender Policy Framework) record, stored as a TXT record in the DNS, is used to validate email senders' authenticity. It specifies which mail servers are allowed to send emails on behalf of a domain, helping to prevent email spoofing and phishing.
Important Key Points:
1. SPF record: The SPF record is a DNS record that defines which mail servers are authorized to send email for a specific domain. It is stored as a TXT record and helps prevent unauthorized senders from impersonating the domain.
2. Email Security: SPF is crucial in enhancing email security by ensuring that only legitimate mail servers can send emails for a domain, thereby protecting against phishing and email spoofing attacks.
3. TXT Record: The SPF record is stored as a TXT record in DNS. While the TXT record can store various types of text information, SPF data is typically stored this way.
Knowledge Booster:
· MX record: The MX (Mail Exchange) record specifies the mail servers responsible for receiving email for a domain. However, it does not verify whether the sender is authorized to send email for that domain.
· AAAA record: The AAAA record maps a domain to an IPv6 address. It is not related to email sender authentication.
· PTR record: A PTR (Pointer) record is used for reverse DNS lookups, mapping an IP address to a domain name. It is not used for specifying authorized mail servers.