The United Kingdom's Behavioral Insights Team Substantially Increased the Amount

The United Kingdom's Behavioral Insights Team substantially increased the amount of income tax collected each year by

A) printing frowning face emoticons on correspondence to delinquent payers.
B) mailing letters to those who had not yet paid, telling them that their neighbors had paid.
C) establishing an automatic payroll withdrawal system to collect taxes.
D) sending delinquent payers pictures of poor children.