The correct answer is C) Human Reason.
Philosophers of the Enlightenment had faith in Human Reason, believing it could answer questions and solve problems.
The Enlightenment period is considered the Age of the Reason. European philosophers in the late 17th century or the beginning of the 18th century considered that human reason was the answer to dissipate the ignorance of the Dark Ages. Philosophers considered new alternatives of knowledge that would improve humanity such as the scientific method, liberty, and reason.