Question

As a car drives by honking its horn, the pitch will be higher as it approaches and lower as it moves away. This is because of.

ultrasound
sonar
echolocation
the Doppler effect

Answer 1

The Doppler effect hope this helps :)$

Answer 2

the Doppler effect

Step-by-step explanation:

the doppler effect states that as something is moving towards you the pitch will be higher and as that thing goes away the pitch will be lower.