(C) is supported in the final paragraph. This paragraph describes how "all individuals have basic, nonlegal duties to one another - duties not to harm others in their lives, liberty, health, or goods," so that "even if governmental laws have no moral force, individuals still have duties to refrain from those actions that constitute crimes in the majority of legal systems" because they prohibit such harms. The passage goes on to give an example that illustrates how people should obey laws to drive on the correct side of the road not because it's the law but because it will prevent harm. Therefore, individuals should support the efforts of the government in preventing harm, even if there is no moral obligation to obey the law simply because it's the law.
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