How can they keep the DRS domain secure?

A administrator has configured memory to memory (M2M) session persistence for a large WebSphere Application Server ND cluster with a dedicated data replication service (DRS) domain.

How can they keep the DRS domain secure?
A . Select encryption type DES and TRIPLE_DES.
B . Select DCS-Secure as transport chain under Core Group name.
C . Nothing needs to be done, the environment is secured when using M2M session persistence.
D . Select encryption type DES and TRIPLE_DES and regenerate the encryption key periodically.

Answer: B