When the delegates met in Philadelphia as the Federal Convention, they realized that both the Articles of Confederation and any amendments that might be proposed to them had to be adopted, or ratified, by all thirteen states' legislatures. This was because of the unanimous consent of the states required by Article 13 of the Articles of Confederation. All attempts to amend the Articles failed, as would the proposed Constitution because of this unanimous vote required. There were three reasons why both earlier amendments to the Articles and the proposed Constitution would fail under Article 13's procedures: First, it was simply impossible to secure unanimous endorsement by all thirteen states of even the simplest amendment -- and the proposed Constitution was far more than a simple amendment to the Articles. Second, the designers of the Constitution realized that the state legislatures would not accept a system that diminished their authority. Third, the designers realized that they were creating a new constitution for a united American people. On the grounds of political and constitutional principle, the state legislatures, as agents of the people of the several states, could not exercise the power to constitute a government on behalf of their citizens, only the people of the several states, or representatives whom they elected solely for that purpose, could exercise that constituent power. 20) According to Article 13 of the Articles of Confederation, what percentage of votes by the states was required to ratify any amendments?

A. 33%, or approximately 1 out of three

B. 13% of the votes

C. a unanimous vote or 100%

D. 50% of the votes