What Is the Primary Drawback to Using Advanced Encryption Standard

What is the primary drawback to using advanced encryption standard (AES) algorithm with a 256 bit key to share sensitive data?

A) Due to the key size, the time it will take to encrypt and decrypt the message hinders efficient communication.
B) To get messaging programs to function with this algorithm requires complex configurations.
C) It has been proven to be a weak cipher; therefore, should not be trusted to protect sensitive data.
D) It is a symmetric key algorithm, meaning each recipient must receive the key through a different channel than the message.