Which two statements are true when configuring OSPF authentication?

Which two statements are true when configuring OSPF authentication? (Choose two.)

A.
An OSPF link can support both simple password and MD5 authentication at the same time.

B.
An MD5 password requires a key ID.

C.
You can configure multiple MD5 passwords simultaneously on the same link.

D.
If the MD5 password negotiation fails, you can configure OSPF to automatically use a simple password as a backup.