Which of the following is an appropriate explanation concerning the usage of a UPS (Uninterrupted Power Supply)?
a) It is used as a spare battery for a cell phone in order to use the cell phone for a longer time.
b) It is used to continue the supply of power when a long power failure occurs in a computer center.
c) It is used to temporarily supply power to a computer when a power failure occurs, and to safeguard the computer against a momentary drop in voltage.
d) It is used to enable the use of a computer for along time in an outdoor area where no other power source is available.