Explanation:

Correct option 3: Pound

Roscoe Pound is known as the "Social Utilitarian" because:

• He emphasized the concept of "social engineering", where law is used as a tool to balance competing interests in society.

• His approach focused on achieving maximum social satisfaction with minimal friction, aligning closely with utilitarian ideals but in a social context.

• Unlike classical utilitarians like Bentham, Pound's utilitarianism centered on society as a whole, not just individual pleasure or pain.

Thus, he earned the label Social Utilitarian for adapting utilitarian principles to social needs and interests.