What is considered best practice for back-end performance on a CX4 and is not enforced by FLARE or Navisphere?

A.
There is no best practice. It depends on the environment.

B.
Up to two (2) BEs and two (2) FEs per FC I/O module

C.
A single BE or FE per I/O module

D.
Up to two (2) BEs and two (2) FEsperiSCSI I/O module