Answer: option A - an increase in the height of the sound wave
Explanation:
Loud sounds are carried by waves that have a higher amplitude (height between peak and trough) than quiet sounds. The bigger the amplitude of a sound wave, the louder it sounds to our ears.
So, the perceived increase in the volume of sound is best explained by an increase in the height of the sound wave
 
        
                    
             
        
        
        
On earth an object at rest has gravity acting on it
        
                    
             
        
        
        
Hello!
It helps the Rabbit walk on top of the snow
        
                    
             
        
        
        
The negative impact humans could have on an ocean ecosystem is pollution, which can lead to a mass extinction on the wildlife.