Final answer:
Correct option is 3) .A UPS (uninterruptable power supply) is used to protect computers from power surges and outages. It regulates excessive voltage and provides backup power during outages to prevent damage and data loss.
Step-by-step explanation:
A UPS (uninterruptable power supply) is used to protect computers from power surges and outages. A power surge is a sudden increase in voltage, which can occur due to lightning strikes or when power is restored after an outage. A UPS can detect and regulate excessive voltage to prevent damage to the computer. On the other hand, a power outage refers to a complete loss of electricity supply, which can cause data loss and disrupt computer operation. A UPS provides backup power during outages, allowing users to save their work and safely shut down the computer.