<em>A. Nine states were required for approval of any changes.</em>
Explanation:
The Articles of Confederation was the first constitution for the United States, even before the United States Constitution. The Articles of Confederation was very weak and gave limited power to the federal government. Under the Articles, the government could not tax the states, regulate trade, draft soldiers, or even create and enforce laws properly.
One of the major weaknesses of the Articles of Confederation was the fact that the government could not amend or create laws easily, which made it hard to unify the country and make the citizens abide by rules. In order to pass any new laws, 9 out of 13 of the states had to agree to it. As you can imagine, it was difficult getting that many states to agree to anything.
Eventually, the Constitutional Convention of 1787 was called. The original goal of the Constitutional Convention was to simply just amend the Articles of Confederation. This did not happen though, as the Articles of Confederation ended up getting thrown out altogether and the United States Constitution was created in its place. With the United States Constitution, it was much easier for the government to create and enforce laws.