Refer to the exhibit. The entire MAC address table for SW1 is shown here:

What does SW1 do when Br-4 sends a frame for Br-2

A. It performs a lookup in the MAC address table for Br-4 and discards toe frame due to a missing entry.
B. It floods the frame out or all ports except on the port where Br-2 is connected.
C. It Inserts the source MAC address and port into the forwarding table and forwards the frame to Br-2.
D. It maps the Layer 2 MAC address for Fa0/3 to the Layer 3 IP address and towards the frame.