The advantage of sending messages using steganographic techniques, as opposed to utilizing encryption, is
that:

A.
the existence of messages is unknown.

B.
required key sizes are smaller.

C.
traffic cannot be sniffed.

D.
reliability of the data is higher in transit.

Explanation:

The existence of messages is hidden when using steganography. This is the greatest risk. Keys are relevant for encryption and not for steganography. Sniffing of steganographic traffic is also possible. Option D is not relevant.