As with any block cipher, AES can be used to construct a message
authentication code, and for this, only decryption is used.

Question

Quizplus · Accepted Answer

AES, as a block cipher, can indeed be used to construct a message authentication code (MAC), but this typically involves encryption rather than decryption. MACs ensure data integrity and authenticity, and while there are modes of operation where decryption might play a role in the verification process, the statement that only decryption is used is incorrect.

As with Any Block Cipher, AES Can Be Used to Construct