The author was, no doubt, ______.

A．attitudes affect our actions
B．teachers play a significant role in developing or changing pupils' attitudes
C．attitudes can be changed by some classroom experiences
D．the elementary school is a more effective milieu for developing wholesome attitudes than high school or college

A．the teacher should guide all discussions by revealing her own attitude
B．children’s attitudes often come from those of other children
C．in some aspects of social studies a greater variety of methods can be used in the upper grades than in the lower grades
D．schools should offer the student opportunities for travel so that he can come into contact with people he would not otherwise meet