Which technique is utilized by the Cyclic Redundancy Check (CRC) for error-checking?

Cyclic Redundancy Check (CRC) employs polynomial division to check for errors in data. This method involves treating data as a polynomial and dividing it by a predefined binary divisor (known as the generator polynomial). The remainder of this division operation is the CRC value, which is appended to the data being transmitted.

When the data is received, the receiver performs the same division with the received data (including the CRC value) to check for any discrepancies. If the remainder is zero, it indicates that no errors occurred during transmission. Thus, option C accurately describes the technique used by CRC, emphasizing the importance of the division by a binary divisor.

Other options do not accurately represent how CRC functions. For instance, calculating a checksum based on a divisor is more aligned with simpler error-checking methods and does not describe the polynomial division approach used by CRC. A time-stamped validation system refers to a different error-checking method that involves timestamps, and sending duplicate packets for verification pertains to redundancy techniques rather than the specific mechanism of CRC error detection.