Scenario: Migrating a stand-alone application storing PII to the cloud.
Data to Encrypt: Data at rest (Option B) should be encrypted:
Data in transit (Option A) and backups (Option C) are also important but not the primary concern here.
Data archives (Option D) may or may not contain sensitive data.

Constant Replication
The primary system replicates data changed data blocks continually. Constant replication is also referred to as "continuous replication." The replication process occurs in the background, permitting users to access the data without interruption.
Constant replication is different than regular backups, where files must be closed to be duplicated.

RAID 0 is a configuration that splits data evenly across two or more disks without parity or mirroring. This improves performance but offers no fault tolerance. If a drive in a RAID 0 array fails, the data on the array becomes inaccessible and the server will immediately crash. The other options are not applicable to RAID 0. Reference: [CompTIA Server+ Certification Exam Objectives], Domain 3.0: Storage, Objective 3.2: Given a scenario, configure RAID using best practices.

Fault tolerance is the ability of a system to continue functioning in the event of a failure of one or more of its components. Fault tolerance can ensure a secondary network path is available if the primary connection fails.
Fault tolerance can be achieved by using redundant components, such as network cards, cables, switches, routers, etc., that can take over the function of the failed component without interrupting the service.
References:
https://www.comptia.org/training/resources/exam-objectives/comptia-server-sk0-005-exam-objectives (Objective 2.2)

KVM-over-IP switches are the remote access version of local KVM (keyboard/video/mouse) devices. They allow administrators to control a remote system by sending keyboard and mouse signals over the network and displaying the remote system's video output on the administrator's local machine via a web browser. Administrators can perform almost any function on the remote system as long as it's powered on and connected to the network.