In a population isolated by a geographic barrier becomes a new species as it accumulates changes by natural selection or genetic drift.

The correct answer is allopatric speciation.

Explanation:

Allopatric speciation occurs when a geographical barrier comes between a species population living in the same area. This geographical barrier separates the population into two different geographical area which do not have the same condition.

So as both the separated population get different habitat environment to live so they evolve differently from each other. So natural selection and genetic drift works differently in both the population which brings genetic changes in the population and helps in creating a new species.

you did not attach the discourse, but i assume it to be the discourse on the origin and basis of inequality among men (the original titile in french is: "discours sur l'origine et les fondements de l'inégalité parmi les hommes"), also know as "second discourse". in this discourse, jean-jacques rousseau emphasizes that private property is the basis of all inequalities.

therefore, what enabled the old regime to maintain as long as it did was private property.