Do you think that the background sounds in movies and video games hav an important effect on listeners? explain

Yes, background sounds in movies and video games have a critical effect on listeners. Oftentimes when a viewer is playing/watching they are visualizing themselves in the act being displayed onscreen (consciously or subconsciously), and their brains are paying attention to things it would define as "normal" if it was really happening to them. For example, if there was a character walking through the woods in fall, a listener's brain would be listening for the crunch of leaves and sticks underneath the character's feet, however, if this sound was absent it is likely that they would notice something was "wrong" with the movie/video game, even if they were unable to pinpoint exactly what was bothering them.

so whats the question?

a is is the correct answer