Bats detect obstacles in their path by receiving the reflected

Bats detect obstacles in their path by receiving the reflected

Infrasonic waves
Ultrasonic waves
Radio waves
Microwaves
This question was previously asked in
UPSC NDA-2 – 2017
The correct answer is Ultrasonic waves.
Bats use a process called echolocation to navigate and find prey in the dark. They emit high-frequency sound waves, which are beyond the range of human hearing (ultrasonic waves). These waves reflect off objects in their path, and the bat detects the returning echoes, interpreting them to build a ‘sound map’ of their surroundings, thus detecting obstacles and prey.
Infrasonic waves are sound waves with frequencies below the human hearing range. Radio waves and microwaves are types of electromagnetic radiation, not sound waves, and are not used by bats for echolocation.