The correct matches are the following.
John Locke - natural rights.
Baron de Montesquieu - checks and balances.
Voltaire - the importance of religious tolerance.
During the Enlightenment period in Europe, brilliant philosophers and thinkers came up with different and innovative ideas about the government and its role in society. Among them, Jhon Locke referred to the natural rights of every single human being that had to be respected by governments. Voltaire emphasized the importance of having religious tolerance to maintain harmony in a society. In the case of Baron de Montesquiou, he suggested a creative form of government based on the system of checks and balances, in which none of the government branches had more power than the other.
Other great thinkers of the Enlightenment were Jean-Jaques Rosseau, Thomas Hobbes, and Diderot.