What are the countermeasures used to keep hackers from using various cryptanalysis methods and techniques?
a. Keys should not be given to the application or the user directly.
b. Use passphrases and passwords to encrypt a key stored on disk.
c. Include keys inside the source code or binaries.
d. Use a key size of 168 bits or 256 bits for symmetric key algorithms.
e. Prohibit the transfer of public keys for certificate signing.