Answer:
b. E-mail relies upon DNS MX records to identify hosts that are responsible for e-mail transmission.
Explanation:
It is important to ensure that Domain Name Servers have been secured before implementing an e-mail system because E-mail relies upon DNS MX records to identify hosts that are responsible for e-mail transmission.
In other word, this helps the DNS MX determines the mail server accountable for receiving email messages on behalf of a domain name.
