When Schultz, Et Al

When Schultz, et al. (2007) included a smiley or frowny face on homeowners' energy bills, people's reactions were consistent with the idea that

A) feedback is ineffective at promoting long-term behavior change.
B) reinforcement generally works better than punishment.
C) descriptive norms are more powerful than injunctive norms.
D) informational feedback is more powerful than social feedback.