The correct answer is because it emphasized force.
Many aristocrats supported legalism because it emphasized force.
Legalism was a philosophy of ancient China that was important during the Warring States time from 471-221 BCE. It was based on the strict application of law, with the idea of increasing political, economic, and social stability.
An aristrocrat was a member of the rich or upper class in a capitalist society. Most of the time its money was the product of heredity or its family is considered part of the nobility. Many of this aristocrats supported legalism because it emphasized force.