Your network contains two DHCP servers. The DHCP servers are named DHCP1 and DHCP2. The internal network contains 1，000 DHCP client computers that are located on a single subnet. A routerseparates the internal network from the Internet. The router has a single IP address on the internal interface. DHCP1 has the following scope information. èStarting IP address： 172.16.0.1 èEnding IP address： 172.16.7.255 èSubnet mask： 255.255.240.0 You need to provide a fault-tolerant DHCP infrastructure that supports the client computers on the internal network. In the event that a DHCP server fails， all client computers must be able to obtain a valid IP address. How should you configure DHCP2？（）

A. Create a scope for the subnet 172.16.0.0/20. Configure the scope to use a starting IP address of 172.16.8.1 and an ending IP address of 172.16.15.254.
B. Create a scope for the subnet 172.16.0.0/21. Configure the scope to use a starting IP address of 172.16.0.1 and an ending IP address of 172.16.15.254.
Create a scope for the subnet 172.16.8.0/21. Configure the scope to use a starting IP address of 172.16.8.1 and an ending IP address of 172.16.10.254.
D. Create a scope for the subnet 172.17.0.0/16. Configure the scope to use a starting IP address of 172.17.0.1 and an ending IP address of 172.17.255.254.