The correct answer is: D) used reason to try to improve people's lives.
The Enlightenment refers to a philosophical movement that took place in England first, and later in North America on the late 17th and early 18th century. It is also called as The Age of Reason, this gives us an important clue to answer the question. In this movement coencepts like reason, liberty and the scientific method were very important, by using the reason to obtain knowledge this philosophers thought they were illumination human intelect and culture, opposed to the dark era of Middle Age. This is one of the reasons they were very skeptical wiht religion, monarchies and hereditary society. Reason would be the one that would finally make the man free.