Which of the following would be MOST appropriate for storing sensitive data in a secure storage environment?

LUN masking restricts which hosts can see specific logical unit numbers in a SAN, controlling access paths but leaving the underlying data unprotected if those controls are circumvented.

ACLs enforce file or network-level permission rules but do not protect the actual data content if the storage media is physically removed or access is gained through another vector.

Encryption uses cryptographic algorithms to transform sensitive data into ciphertext, ensuring confidentiality even if physical media is stolen or logical access controls are bypassed. It is the only control among the choices that directly protects the data itself rather than controlling access paths to it. This makes it the primary security mechanism for sensitive data at rest in any storage environment.

Zoning segments Fibre Channel SAN fabrics to control which devices can communicate, but it does not encrypt or otherwise protect the content of the stored data itself.