Explanation
LTS (Long Term Support) is the update branch that the administrator should choose to ensure the system receives updates that are maintained for at least four years. An update branch is a category or group of updates that have different characteristics or features, such as frequency, stability, duration, etc. An update branch can help customers to choose the type of updates that suit their needs and preferences. LTS is an update branch that provides updates that are stable, reliable, and secure, and are supported for a long period of time, usually four years or more. LTS can help customers who value stability and security over new features or functions, and who do not want to change or upgrade their systems frequently.

Explanation
RAID 5 is a disk array configuration that uses parity to provide fault tolerance and data recovery. RAID 5 can tolerate the failure of one disk, but not two or more disks. If a second disk fails during the resynchronization process, the data on the RAID 5 array will be lost and unrecoverable. The only way to make the server fully operational is to restore the data from a backup source.

Explanation
SHA-512 is a tool that can generate a cryptographic hash value for any given data. A cryptographic hash value is a fixed-length string of bits that uniquely and irreversibly represents the data. SHA-512 is one of the variants of the Secure Hash Algorithm 2 (SHA-2) family, which is a widely used and standardized hash function .
SHA-512 can help users to verify software integrity by comparing the hash values of the software before and after downloading, installing, or transferring. If the hash values match, it means that the software has not been altered, corrupted, or tampered with. If the hash values differ, it means that the software may have been compromised, infected, or damaged .

Explanation
Enable MFA with a one-time password. MFA stands for multi-factor authentication, which is a method of verifying a user's identity by requiring two or more forms of authentication. A one-time password (OTP) is a code that is generated randomly and valid only for a short period of time. By enabling MFA with OTP, the administrator can make access to the SaaS email more secure without changing the password policy, as users will need to provide both their password and an OTP to sign in.

Explanation
System hardening. System hardening is the process of securing a system by reducing its surface of vulnerability, which is larger when a system performs more functions. In contrast to system hardening, which is performed once, patch management, vulnerability scanning, and log monitoring are ongoing processes. By hardening the VDI instances, the provider can prevent users from installing prohibited software or making unauthorized changes to the system configuration. This can be done by applying security policies, disabling unnecessary services, removing default accounts, and enforcing strong passwords. For more information on system hardening, you can refer to the CompTIA Cloud+ CV0-003 Certification Study Guide1 or the CompTIA Cloud+ (Plus) Certification website2.