Which of the following commands will configure a router…

Which of the following commands will configure a router to use DNS for hostname resolution?

A.
ip dns primary

B.
ip domain lookup

C.
ip dns server

D.
ip name-server

Explanation:
The ip domain lookup command configures the device to use DNS for hostname resolution. It must be accompanied by a command that specifies the location of the
DNS server, which is done with the ip name-server command.
The ip dns-primary command is used to configure the device as the primary DNS name server for a domain (zone) and as the start of authority (SOA) record
source, which designates the start of a zone.
The ip dns server command is used to make the device a DNS server.
Objective:
Infrastructure Services
Sub-Objective:
Describe DNS lookup operation

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_dns/configuration/15-mt/dns-15-mt-book/dns-config-dns.html