What would most likely help mitigate phishing and spear-phishing attacks within a company?

The correct choice is the implementation of DNSSEC (Domain Name System Security Extensions) and DMARC (Domain-based Message Authentication, Reporting & Conformance).

DNSSEC adds a layer of security to the DNS protocol by enabling the verification of the authenticity of the responses to DNS queries. This helps prevent attackers from redirecting users to malicious websites, which is often a tactic used in phishing attacks. By ensuring that communications are coming from legitimate DNS servers, DNSSEC helps safeguard users against fraudulent domain names that could lead to phishing sites.

DMARC, on the other hand, is an email authentication protocol that helps protect email senders and recipients from spam, phishing, and spoofing. It allows domain owners to specify how unauthenticated emails should be handled by the receiving mail servers, providing instructions for their rejection or marking them as spam. This reduces the chances of an employee falling victim to phishing or spear-phishing attacks by ensuring only legitimate emails are delivered to their inboxes.

In contrast, while DNS query logging, exact mail exchanger records, and DNS conditional forwarders can contribute to overall network management and troubleshooting, they do not directly address the critical vulnerabilities exploited by phishing and spear-phishing. These options do not provide the same level of protection against social engineering