The answer to your question is:
SSH v1.x and v2 are entirely different protocols and are not compatible. SSH v1.x is supported by the PIX firewall.
You can use either DES or 3DES or even AES (Advanced Encryption Standard) for SSH.
You need to generate RSA key on the PIX for use with SSH.
So you are correct in your assumption that the answer is A and C.
Testking answers are NOT reliable, trust me!!
If you are preparing for taking the CCSP (642-521) exam, then I would recommend that you purchase the following book:
CCSP Self-Study 2nd Edition by Behzad Behtash (Cisco Press) ISBN: 1-58705-149-4
Good luck with your studies and please rate post if it helps.
Jay