Answer: b. DNSSEC
Explanation:
From the question, we are informed that company wants to host a publicity available server that performs the following functions such as evaluates MX record lookup, can perform authenticated requests for A and AAA records, uses RRSIG.
To fulfill the above requirements, the company should use Domain Name System Security Extensions (DNSSEC). It should be ited that DNSSEC is simply an suite used for securing some information that have been provided by
the DNS.
