You Walk into Your Next Class and See the Following

You walk into your next class and see the following written on the board: "Differences are not disorders." You find out that the class that met in this classroom was a psychology class. What was the point of the class?

A) We should avoid culturally biased interpretations.
B) The mentally ill deserve the same rights as the rest of the population.
C) Laws restricting the ability of the mentally disabled to marry are misguided.
D) We should not look down upon those whose level of intellectual functioning is below ours.