Which network server is malfunctioning if a user can ping the IP address of a web server but cannot ping the web server host name?

Which network server is malfunctioning if a user can ping the IP address of a web server but cannot ping the web server host name?

• the DHCP server
• the DNS server
• the FTP server
• the HTTP server
  

  Explanation: If pings are successful to an IP address but not to a host name, then the problem may be that a DNS server cannot be accessed.