The correct answer is A. UPS.
A UPS (Uninterruptible Power Supply) is a device that provides emergency power to a computer or other electronic equipment during a power outage. A UPS typically contains a battery that can provide power for a short period of time, typically 10-30 minutes. This is enough time to save your work and shut down your computer properly.
A UPS can also protect your equipment from power surges and spikes. A power surge is a sudden increase in voltage, while a power spike is a brief increase in voltage. Both of these can damage your equipment. A UPS will filter out these spikes and surges, protecting your equipment from damage.
Proper grounding is important for safety, but it will not protect your equipment from power outages or spikes. A surge protector is a device that can protect your equipment from power surges, but it will not protect it from power outages. A sag protector is a device that can protect your equipment from power sags, but it will not protect it from power outages or spikes.
Therefore, the only option that can ensure power is not interrupted, resulting in corrupted data is A. UPS.