Your IT team disabled numerous ports on the external firewall due to a recent security compromise. Users can no longer access websites by URLs, but they can do so via IP addresses. What port(s) must the IT team reopen in order to provide Internet access via URLs?

Clients can't reach the DNS server, which converts hostnames (or URLs) to IP addresses. Port 53 is used by DNS. File Transfer Protocol (FTP) uses ports 20 and 21. Dynamic Host Configuration Protocol (DHCP) uses ports 67 and 68. Hypertext Transfer Protocol (HTTP) uses port 80, and HTTP Secure (HTTPS) uses port 443.