Answer:
It drops the frame
Explanation:
The FCS stands for the frame check sequence, and it is nothing else but an error-detecting code which is added to the frame ( communication protocol). However, the frames are being used for sending the payload data via a source to a certain destination. And if the CRC is not correct, or that does not match the CRC of the FCS then it confirms that the sequence is not correct, and FCS drops that frame.