What is the source of morality according to natural law theory?

The correct answer is C. Nature.

Natural law theory posits that morality is derived from human nature and the world around us. It suggests that moral principles are inherent in the natural order and can be discovered through reason. According to this view, what is “natural” is inherently good and provides a foundation for moral judgment. This contrasts with morality being derived from external sources like revelations, culture, or scripture.