Explanation
Generators are considered an external redundancy to a data center. Power distribution units (PDUs), storage systems, and power feeds to racks are all internal to a data center, and as such they are considered internal redundancies.

Explanation/Reference:
Explanation:
In order to ensure compliance with regulations, it is important for an organization to regularly test the restorability of archived data. As technologies change and older systems are deprecated, the risk rises for an organization to lose the ability to restore data from the format in which it is stored. With the destroy, store, and share phases, the currently used technologies will be sufficient for an organization's needs in an ongoing basis, so the risk that is elevated with archived data is not present.

Explanation
AES is an encryption standard. Link encryption is a method for protecting communications traffic. One-time pads are an encryption method.

A network-based IDS has the advantage of being segregated from host systems, and as such, it would not be open to compromise in the same manner a host-based system would be. Although a network-based IDS would be external to system patching, this is not the best answer here because it is a minor concern compared to segregation due to possible host compromise.
Scalability is also not the best answer because, although a network-based IDS does remove processing from the host system, it is not a primary security concern. Network access is not a consideration because both a host-based IDS and a network- based IDS would have access to network resources.