According to Article 1, Section 10, what are states prohibited from doing?

The correct choice regarding what states are prohibited from doing according to Article 1, Section 10 of the United States Constitution is creating their own currencies or treaties. This provision is crucial as it establishes the exclusive powers of the federal government in regulating currency and foreign relations. By prohibiting states from issuing their own currency, the Constitution aims to maintain a stable and uniform monetary system across the entire nation, preventing the economic chaos that could arise from multiple currencies in circulation. Additionally, restricting states from entering into treaties helps prevent conflicting foreign policies that could undermine national unity and diplomatic relations.

The constitution's framers recognized that a divided approach to currency and international agreements could lead to fragmentation and disputes among states, which is why these prohibitions are essential in maintaining the integrity and authority of federal governance. This framework ensures that the federal government exclusively handles matters that affect the nation as a whole, such as international commerce and relationships.