Backups are crucial in system administrations for preserving continuity and protecting against specific types of hardware failures, service interruptions, and human mistakes. To aid a company in recovering from an unexpected catastrophe, backup copies make it possible to restore data to a previous point in time. To safeguard against primary data loss or corruption, it is essential to save a copies of data on a different media. When a system administrator create a backup, he makes a copy of the data that you can restore if your main data is lost. These errors may be the consequence of faulty hardware or software, corrupted data, or a human error like a targeted attack or an unintentional deletion. System backup and recovery is therefore a crucial skill for system administrators as well as the companies they work for.
Three methods for performing backup:
Disk image: A efficient method to back up not only the files and directories but also everything else on the system is by creating a disk image. If a user have a disk image, the user can restore everything, including the operating system, applications, data, and more, so the user won't have to worry about any difficulties. Placing the disk image-containing DVD into the DVD-ROM to restore the backup. Additionally, just attach an external HDD to the computer if the user have a disk image that they made.
External hard drive: The most common backup method is to use an external hard drive or even a USB flash drive. An HDD can be easily, quickly, and affordably backed up. It is effective since consumers may carry their portable backup with them wherever they go.
Cloud backup: Cloud backup or Online backup has been around for a while, but not many people really utilize it. But the greatest backup technique by far is cloud backup. The user does not have to worry about hardware problems because their files are saved in the cloud and can be accessed from anywhere because the backups are automatically produced and everything is synchronized. It is one of the greatest methods to backup, especially when you consider that the contents are encrypted and stored securely.
Return on investment (ROI) is defined as term that measures the performance of single investment efficiency or numerous investment plans. It evaluates and assess plan of investment in form of ratio or percentage.
Return of investment(ROI) plan is calculated through dividing the return of investment by investment cost.
Other options are incorrect because cash return on capital invested ,carried forward(CF) and BI (business intelligence) are not used for calculating the investment plan through cost and benefit.Thus, the correct option is option(c)