Error detection at the data link layer is achieved by

The correct answer is Option C: Cyclic redundancy code (CRC). At the data link layer, error detection is crucial to ensure that frames transmitted over a network have not been corrupted during transit. CRC is the industry-standard technique used for this purpose because it generates a checksum based on polynomial division, allowing the receiver to detect accidental changes to raw data with high reliability. While Hamming codes (Option A) are primarily designed for error correction rather than simple detection, and bit stuffing (Option B) is a technique used for framing synchronization to prevent flag patterns from appearing in the data, neither serves as the primary mechanism for error detection. Therefore, CRC is the definitive choice implemented in protocols like Ethernet and Wi-Fi to maintain data integrity at this layer.