What did Horace Mann argue about a school's responsibility in reinforcing social stability in relation to students' discipline instilled by their parents?

a. It was not a school's responsibility to rescue students from parents' failure in disciplining them
b. Schools should prioritize educating students, not compensating for parents' shortcomings
c. Mann believed in the autonomy of parents in disciplining their children
d. He argued that social stability was not the school's concern
e. He emphasized the importance of individual and parental responsibility in character formation