Knowing about the effects of the perceived distance of objects on their perceived size us to understand

Size constancy

Explanation:

Size constancy is the perception that defines the object that having the same size when it perceived rather than what image created on the retina that accomplished the distance from objects. So that we tend to see the object in the same size despite the size that occurs on the retina.  

For instance, when we see the car from the 10th floor of building it seems like a toy but even then we know its exact size because of size constancy.  

answer; i believe the correct answer is customer,manufacturer, service provider,general public ; quality is primarily the responsibility of all all employees in the organization.