What helps avoid split brain in active / passive high availability (HA) pair deployment?

What helps avoid split brain in active / passive high availability (HA) pair deployment?
A . Enable preemption on both firewalls in the HA pair.
B . Use a standard traffic interface as the HA3 link.
C . Use the management interface as the HA1 backup link
D . Use a standard traffic interface as the HA2 backup

Answer: C