Question

question 18
what is the purpose of the fcs field in a frame?
to compute the crc header for the data field
to verify the logical address of the sending node
to determine if errors occurred in the transmission and reception
to obtain the mac address of the sending node

Explanation:

The Frame - Check Sequence (FCS) field in a frame is used for error - detection. It contains a value (usually calculated using a cyclic redundancy check, CRC) that helps the receiving device determine if the data has been corrupted during transmission.

Answer:

to determine if errors occurred in the transmission and reception