Which of the following is not a weakness of symmetric cryptography?

A.
Limited security

B.
Key distribution

C.
Speed

D.
Scalability

Explanation:
In secret key cryptography, a single key is used for both encryption and decryption.
The sender uses the key (or some set of rules) to encrypt the plaintext and sends the cipher text to
the receiver. The receiver applies the same key (or rule set) to decrypt the message and recover
the plaintext. Because a single key is used for both functions, secret key cryptography is also
called symmetric encryption.
With this form of cryptography, it is obvious that the key must be known to both the sender and the
receiver; that, in fact, is the secret. The biggest difficulty with this approach, of course, is the
distribution of the key.
Symmetric encryption is around 1000 times faster than Asymmetric encryption, the second is
commonly used just to encrypt the keys for Symmetric Cryptography.