Natural rights typically refer to the philosophical idea that individuals possess inherent rights simply by being human. These rights are thought to be universal and not granted by any government or authority. They often include the rights to life, liberty, and property.
The most fitting response from your listed options would be:
reasoning why people might create a government in the first place.
This aligns with the notion that individuals enter into a social contract to form governments to protect their natural rights, establishing legitimacy and authority based on the fundamental rights of individuals.