Answer:
A. Common people.
Step-by-step explanation:
The Enlightenment thinking, which emphasized science and reason over faith and superstition, was a threat to those who gained their power by divine right or from the Church. Therefore, it posed a threat to Monarchs, Nobles, and Priests who held power in society.
On the other hand, the common people were not threatened by Enlightenment thinking. In fact, Enlightenment thinkers like John Locke and Isaac Newton spread new ideas about openness, investigation, and religious tolerance2, which could be seen as beneficial to the common people. So, the answer is A. Common people.