If you present a pro-life speech and get the pro-choice listeners to feel uncomfortable with their positions, you have effectively used the persuasive technique of:
a. negative motivation.
b. appealing to basic human needs.
c. emotional appeal.
d. cognitive dis-sonance.

d. cognitive dissonance.  

Explanation:

Cognitive dissonance: In psychology, the term cognitive dissonance was introduced by Dr. Leon Festinger, which provides insight into individuals for self-persuasion.

According to Festinger, when an individual makes a decision about something he or she feels worried whether he or she has made the right decision or not. The main cause of persuasion related to cognitive dissonance is self-talk to the audience being persuaded instead of the massage's content.

Cognitive dissonance is considered psychologically uncomfortable for an individual to gain consonance.

In the question above, the given statement signifies the use of cognitive dissonance.

c. reserves power to the states and people