Refer to the exhibit.

By default, FortiOS creates the following DHCP server scope for the FortiLink interface as shown in the exhibit.
What is the objective of the vci-string setting?
Refer to the exhibit.
By default, FortiOS creates the following DHCP server scope for the FortiLink interface as shown in the exhibit.
What is the objective of the vci-string setting?
The objective of the vci-string setting is to restrict the IP address assignment to FortiSwitch and FortiExtender devices. This setting ensures that only devices identifying themselves with the specified Vendor Class Identifier (VCI) strings 'FortiSwitch' and 'FortiExtender' will be able to obtain an IP address from this DHCP server scope. This mechanism helps in managing and securing the network by allowing only specific devices to get IP addresses from the DHCP server.
page 209 of study guide
C, as per p. 209 study guide