Which of the following is the first step in configuring a Cisco router as a DHCP server?

A) Use the ip dhcp excluded-address first last command in global configuration mode to list addresses that should be excluded.
B) Use the default-router address1 address2… command in DHCP pool configuration mode to define default router IP address(es) in that subnet.
C) Use the lease days hours minutes command in DHCP pool configuration mode to define the length of the lease, in days, hours, and minutes.
D) Use the domain-name name command in DHCP pool configuration mode to define the DNS domain name.

A
Explanation: A) The addresses excluded from the DHCP pool (via the ip dhcp excluded-address first last command) need to be established before any addresses in this pool are leased.