Question

why was it threatening to the united states that one or more of the states could declare that they would disregard federal legislation?

o because it would give rich states more power than poor states
o because it would create the need for greater enforcement authority
o because such acts could dissolve the union itself
o because it would make one state superior to another

Explanation:

The United States is a federal union. If states could disregard federal legislation, it undermines the unity and authority of the federal government. This could lead to a breakdown of the Union as states act independently. Options A and D focus on state - to - state power imbalances which are not the core threat. Option B about enforcement authority is a secondary concern compared to the potential dissolution of the Union.

Answer:

C. because such acts could dissolve the Union itself