What challenged the old structure of French society?

Ideas of merit and equality

The governing concept is the conflict between birth-based privilege and modern ideas of equality. Under the old order, the First and Second Estates enjoyed important privileges because of their status by birth, while the Third Estate carried much of the tax burden. Enlightenment thinkers and members of the emerging middle class argued that merit, ability and equal rights should matter more than hereditary rank. These ideas challenged the traditional social hierarchy even before revolutionary political changes occurred. Expanding hereditary privilege would strengthen the old structure, and tax exemptions would preserve inequality. Stable bread prices might ease hardship but would not directly question the social order. Thus option A is correct.

This is a Class 9 History question. Chapter: The French Revolution. Topic: French Society During the Late Eighteenth Century.