In the 1960s, new evidence support the theory of continental drift and change it into the theory of plate tectonics. what was this new evidence? rock patterns and glacial deposits in similar climates. the african and south american coastlines are similar, providing evidence of their common origin. fossils disproving the continent of pangaea. the location of the plates was determined by locating their boundaries, using data on the earth’s magnetic field.

I would have to say the first option.

Due to the fact that Africa and South America do not have similar coasts, fossils prove that used to be the continent of Pangaea, and location of the plates had boundaries, but they were not affected by Earth's magnetic fields.

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.