With regard to the implementation of an ILM tiered storage solution, which of the following statements is true?

A.
All mission critical data must be placed in the highest storage tier.

B.
There should be an association of data classification with storage tiers.

C.
There should be up to five storage tiers in a fully implemented ILM solution.

D.
Both data classification and storage tiers are essential to all ILM implementations.