Which of the following is the correct definition of cognitive dissonance?a. a state of tension that occurs when a person's behavior does not correspond to his or her attitude. b. the tendency for members of a group to avoid taking responsibility for their actions because they assume that others will do so. c. the tendency for members of a close-knit group to think alike for the sake of harmony and to suppress disagreement. d. a belief that a statement is true just because the person has heard it repeated over and over again.

Cognitive dissonance is concept of social psychology. It is the discomfort that a person feels due to having conflicting values, beliefs and ideas at the same time, in such a state people feel anger, guilt, dread and surprise. They also have a motivational drive to reduce dissonance to get of that unpleasant state.

Leon Festinger developed cognitive dissonance theory to explain and predict the reaction of people in this situation. This theory states that people have bias to seek harmony between reality and expectations, he termed this process as dissonance reduction.