Which server translates domain names into IP addresses?

The correct answer is the Domain Name System (DNS) server, which plays a crucial role in network communication by translating human-readable domain names, such as www.example.com, into IP addresses, which are required for routing data across the internet. This translation is essential because while people use domain names for ease of remembrance and navigation, computers and networking devices communicate using IP addresses.

The DNS server maintains a database of these mappings and responds to queries from clients (like web browsers) that want to resolve a domain name into its corresponding IP address, thus enabling them to connect to the appropriate server hosting the website or service. This process is fundamental to the functioning of the internet, as it allows users to access resources without needing to memorize complex numerical addresses.

The other options refer to different network functionalities: DHCP servers are responsible for dynamically assigning IP addresses to devices on a network; a default gateway serves as an access point to another network, typically the internet, but does not perform name resolution; and ICMP is a protocol used for sending error messages and operational information but does not translate domain names.