The correct option is (a) Distant Target Object
The best explanation: The Ultrasonic Sensor uses sound Waves of very high frequency to locate and track objects that are in it’s range. The advantages of this technique is that since we are using sound Waves, other factors like most, or fog or anything that causes low visibility become immaterial. However, the only problem is since the sound Waves are propagated at every direction from the source, they become weak as the distance increases and so they are inefficient in dealing with long distance targets.