Arthur did not work very hard on his last class essay assignment, so he was relieved at first to find that he had gotten a c. but when he learned that most of his classmates had gotten b's and a's, he felt unhappy and angry about his grade. arthur's experience is best explained in terms of

the relative deprivation principle                        

Explanation:

Relative deprivation theory or principle: Developed by Samuel Stouffer during World War II.

Relative Deprivation Theory: The theory explains the view of social movements and change, in which different individual takes action for a social change to obtain something like status, wealth, etc that other individual already have and they tend to believe that they should possess too.

In other words, everyone is surrounded by people whom they idealize and with whom they compare themselves and relative deprivation occurs when a person feels inferior to the person he or she idealizes and this often leads to aggression and frustration.

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.