Given the diagram below, complete the missing configuration command in order to make the static NAT functional.

Configuration snippet
R1# show running-config
interface FastEthernet0/0
ip address 192.168.1.3 255.255.255.0
ip nat inside
interface GigabitEthernet0/0
ip address 190.2.2.21 255.255.255.0
ip ____________________ (missing command)
ip nat inside source static 192.168.1.2 200.1.1.2
ip nat inside source static 192.168.1.1 200.1.1.1

(A) nat source
(B) nat enable
(C) nat address
(D) nat outside

nat outside is the correct answer.

The final configuration command should be like this:
interface FastEthernet0/0
ip address 192.168.1.3 255.255.255.0
ip nat inside
interface GigabitEthernet0/0
ip address 190.2.2.21 255.255.255.0
ip nat outside
ip nat inside source static 192.168.1.2 200.1.1.2

Static NAT configuration requires only a few configuration steps. Each static mapping between a local (private) address and a global (public) address must be configured. In addition, because NAT may be used on a subset of interfaces, the router must be told on which interfaces it should use NAT. Those same interface subcommands tell NAT whether the interface is inside or outside. The specific steps are as follows:

Step 1. Use the ip nat inside command in interface configuration mode to configure interfaces to be in the inside part of the NAT design.

Step 2. Use the ip nat outside command in interface configuration mode to configure interfaces to be in the outside part of the NAT design.

Step 3. Use the ip nat inside source static inside-local insideglobal command in global configuration mode to configure the static mappings.