The form of federalism that existed from 1789 to 1945 was described as

A: dual federalism.

What are your other choices?

To determine the correct answer, let's break down the question and explore the options provided.

The question is about the form of federalism that existed in the United States from 1789 to 1945. Federalism is a system of government in which power is divided between a central authority (in this case, the federal government) and regional or state governments.

Now, let's examine the options:

A: Dual Federalism - Dual federalism, also sometimes called "layer cake federalism," refers to a system where the powers and responsibilities of the federal government and state governments are clearly defined and separate from each other. In this system, the federal government primarily focuses on national issues, while state governments handle local matters.

Based on the timeframe given (1789 to 1945), the correct answer is indeed option A: dual federalism.

To arrive at this answer, you can analyze the historical context. From the establishment of the United States as a nation in 1789 through the end of World War II in 1945, there was a clear division of power between the federal government and state governments. The federal government's sphere of influence was limited to matters explicitly outlined in the United States Constitution, while state governments had significant autonomy in their respective jurisdictions.

It's important to note that this form of federalism began to change in the 1930s during the New Deal era, as the federal government expanded its role and powers to address the Great Depression. After World War II, the system transitioned to a more cooperative, intergovernmental model known as cooperative federalism.