Answer:
The concept illustrated is prejudice.
Explanation:
Prejudice refers to a negative opinion of an individual or collective, without real previous knowledge and usually bordering on racism. It is often based on previous customs and traditions about a certain group.
These opinions generally generate a hostile attitude towards the individual or collective and they are usually based on stereotypes.
One of the main concepts presented throughout the film is the stereotype of each character who <em>belongs to a certain group</em>. As Brian's essay states at the beginning of the film, we have a <em>jock, a princess, a criminal, a basket case and a nerd. </em>
Since these students don't interact with people outside of their circle, their <em>idea of each other is based on </em><em>stereotypes</em> and thus develops into prejudice against them.
Andrew thinks Bender is beneath him, implying that "he doesn't even count" and if he disappeared it wouldn't make a difference since he is a criminal. He is being prejudicial against Bender.