When HostA wants to send data to HostC, the following steps occur:

HostA checks if HostC is in the same subnet:

HostA and HostC are in different network segments, meaning HostA must send the packet to its default gateway (RTA, G0/0/0) to reach HostC.

HostA needs the MAC address of its gateway (RTA G0/0/0):

Since ARP (Address Resolution Protocol) is used to resolve IP to MAC addresses, HostA will send an ARP Request to obtain the MAC address of G0/0/0 of RTA.

RTA forwards the packet to HostC:

Once HostA sends the packet to RTA (using G0/0/0's MAC), RTA will route it to the correct network segment and send it to HostC through G0/0/1.

Why the Other Options Are Incorrect:

Option A (HostC) - Incorrect:

HostA does not send an ARP request for HostC because HostC is in a different subnet.

Option B (G0/0/1 of RTA) - Incorrect:

HostA only communicates with its directly connected gateway (G0/0/0), not G0/0/1.

Option C (SWA) - Incorrect:

Switches (SWA, SWB) operate at Layer 2 and do not require ARP.

Final Answer: D (G0/0/0 of RTA)