Answer:
b. a facility must comply with required standards and address the addressable ones as needed.
Explanation:
Required standards are those requirements which a facility is obliged to comply to if it really has to operate. Failure to observe a required standard directly replicayes to breaking of rules.
On the other hand, addressable standards are the requirements which are put in place to allow for some room for the covered entities with regard to their compliance with the set standards.