Based on the Ideas of Adam Smith, It Is ______

Based on the ideas of Adam Smith, it is ______ dentists clean and repair teeth, but ______.

A) not out of benevolence that; from their regard for their own self-interest
B) out of benevolence that; sometimes from their regard for their own self-interest
C) not out of self-interest that; out of their benevolence
D) from charity and good will that; only if they can charge high prices