The tendency for observers to underestimate the impact of the situation and to overestimate the impact of personal dispositions on another's behavior is called the foot-in-the-door phenomenon.
a) the fundamental attribution error.
b) cognitive dissonance.
c) central route persuasion.

Fundamental attribution error

Explanation:

Fundamental attribution error also called over attribution error. It is the tendency to overestimate or emphasis the personality-based explanation for the behavior being observed by others. The person underemphasizing the situational explanation.  

A person becomes biased and judges the person based on behavior rather than the situational factor.  

This phenomenon was proposed by Lee Ross.

well considering i can't see the graph, it's probably prices