In the /etc/resolv.conf file are entries that describe where DNS queries can resolve names to IP addresses. Given a DNS server with an IP of 192.168.33.254, type the exact enry that should appear in this file:

Answer: nameserver 192.168.33.254

Explanation:
From the man pages:
nameserver Name server IP address
Internet address (in dot notation) of a name server that the resolver should query. Up to MAXNS (currently 3, see <resolv.h>) name servers may be listed, one per keyword. If there are multiple servers, the resolver library queries them in the order listed. If no nameserver entries are present, the default is to use the name server on the local machine. (The algorithm used is to try a name server, and if the query times out, try the next, until out of name servers, then repeat trying all the name servers until a maximum number of retries are made.)