What does Jerry need to change to allow a remote site to connect to a web server after an address change?

To enable a remote site to connect to a web server after its address has changed, Jerry needs to update the Domain Name System (DNS) records. DNS serves as the phonebook of the internet, translating human-readable domain names (such as www.example.com) into IP addresses that computers use to identify each other on the network.

When the web server's address changes, the corresponding DNS entries must be updated to reflect this new address. This ensures that all requests made to the domain name are directed to the correct IP address of the web server. Until the DNS records are updated, users trying to access the web server through its domain name may encounter connectivity issues, as their requests will be sent to the outdated IP address.

In contrast, the other options—NTP (Network Time Protocol), STP (Spanning Tree Protocol), and API (Application Programming Interface)—do not pertain directly to resolving or updating network addresses for web access. NTP is used for time synchronization, STP is related to preventing loops in network switching, and APIs are used for enabling communication between applications rather than for managing network address changes.