$19.$ Continuing with the network in Question $(18),$ if machine D sends an ARP request with destination MAC address FF$-$FF$-$FF$-$FF$-$FF$,$ then one of the following is correct:a$.$ Both routers and switches will receive the ARP requestb. Only the targeted device will receive the ARP request C$.$The ARP request will contain MAC addresses, but no IP addressesd. The ARP request helps in learning the MAC address of any machine in LAN $1$ Or LAN $3$e$.$If Router $1$ is targeted with this ARP request, it will respond specifying its MAC address