Which Teenager Is Most "At-Risk" for Engaging in Delinquent Behaviour

Which teenager is most "at-risk" for engaging in delinquent behaviour?

A) Ben, who spends a lot of supervised time at home
B) Ellis, whose parents utilize very consistent discipline techniques
C) Kevin, who is unable to significantly delay his need for personal gratification
D) Grover, whose parents and other close relatives seldom display aggressive behaviour