Which of the following is the BEST way to minimize the downtime?

The DNS administrator needs to change the IP address of the primary Webserver. Any downtime would have a major impact. Which of the following is the BEST way to minimize the downtime?

A.
Update /etc/resolv.conf on the Webserver.

B.
Change the Webserver TTL (Time-To-Live) record to 5 minutes.

C.
Change the Webserver PTR record to the new hostname.

D.
Notify the domain registrar of the change in advance.