Final answer:
The job intended for God's chosen people was to serve as a light to the nations, which involved living according to the worship and laws of Yahweh and serving as a moral and ethical example to other nations.
Step-by-step explanation:
The role of God's chosen people, often referred to as the Israelites, included various responsibilities and was characterized by a distinct relationship with the divine. When addressing the question of what job God's chosen people, the royal priesthood, and God's special possession were supposed to do, the most accurate answer is not to build a mighty empire (A), conquer surrounding nations (B), or fulfill the Great Commission (D), but rather to serve as a light to the nations (C). This is a biblical concept which suggests that the Israelites were meant to exemplify a life dedicated to the worship and laws of Yahweh and in turn influence other nations by their example.
The biblical narrative shows, especially during the reigns of Kings David and Solomon, an emphasis on establishing a kingdom that was both spiritually devoted and ethically bound by the laws given to them, such as the 10 Commandments brought forward by Moses. This would include establishing a just society that worshipped Yahweh exclusively and adhered to a set of moral and ethical guidelines. Contrary to building empires for earthly dominion, the focus was on creating a society that would reflect God's values and act as a model for other peoples.