Suppose that you are watching a movie. Two men are talking, and the camera focuses on a man in a blue shirt, with long sideburns. The focus shifts to the other man. Then it returns to the man in the blue shirt-but now his sideburns are about an inch shorter. If you fail to notice that he looks different, you are exhibiting ____________.
a. bottom-up processing.
b. change blindness.
c. the principle that face recognition is "special."
d. the recognition-by-components approach.

Change blindness is defined as situation where alteration in visual stimulus takes place but gets unnoticed by the observer. Change blindness usually occurs in situation where visual rapidly flickers, attention of observer is moved etc.This causes distraction is careful observation of person.

According to the question,if a person fails to notice shorter length of sideburns because switching of focus from one man to another caused distraction in attention .Thus, it is a case of change blindness.

Other options are incorrect because face recognition, component oriented recognition and bottom-up process is not depicted through question's scenario.Thus, the correct option is option(b).