I’ll give brainliest! match the changes in sound wave properties with their effects on an observer. a. rising pitch b. rising volume c. declining pitch 1.rising frequency 2.rising amplitude 3.longer wavelengths

The answers are:
A:1
B:2
C:3

In short, they are already arranged. 

Pitch is defined as the sensation of a frequency. A high frequency corresponds to a high pitch. Low frequency corresponds to low pitch. So it is right to assume that rising frequency will cause a rising pitch. 

Amplitude  is defined by the loudness of sound. It is the size of a vibration. The bigger the vibration is, the louder the sound it will produce. So it is safe to say that rising amplitude will result in rising volume. 

Wavelength is the distance between the trough of one wave and the trough of the next wave; or the crest of one wave and the crest of the next wave. Short wavelengths mean more waves pass through a certain point at a certain time. As a result, shorter waves create higher frequencies. Longer waves, on the other hand, create lower frequencies. And using the definition of pitch above, we can then say that longer wavelengths will result in declining pitch.