What does a Layer 2 switch do if it receives a frame with a destination MAC address that is not found in its MAC address table?（）

• A、The frame is dropped.
• B、The frame is addressed with a broadcast MAC address and sent out all ports.
• C、The frame is sent out all ports except the receiving port.
• D、An ARP request is sent out all ports except the receiving port.
• E、A destination unreachable message is sent back to the source address.
• F、None of the above.