The correct option for this scenario is E. Reservation. DHCP reservations allow the administrator to assign a specific IP address to a device based on its MAC address. This ensures that the device always receives the same IP address from the DHCP server.
Dynamic assignment: This is the default behavior of DHCP, where IP addresses are assigned dynamically from a pool of available addresses.
Static IP on the server: This is not related to DHCP reservations. A static IP address is manually configured on the device itself, not assigned by the DHCP server.
IP helper: IP helper is used to forward DHCP requests across different subnets, but it doesn't specifically address MAC-based IP assignment.
Exclusion range: Exclusion ranges are used to prevent certain IP addresses from being assigned dynamically by DHCP. They do not assign specific IP addresses based on MAC addresses.
Reservation: DHCP reservations allow the administrator to assign specific IP addresses to devices based on their MAC addresses. This ensures consistent IP assignments for specific devices.
Reference:
CompTIA Network+ Certification Exam Objectives