Final answer:
The fall of 1786 saw events like Shays' Rebellion that raised questions about the effectiveness of the Articles of Confederation due to their inability to address military and economic challenges.
Step-by-step explanation:
The fall of 1786 witnessed several developments that led many to question the effectiveness of the Articles of Confederation. One significant event was Shays' Rebellion, an uprising of Massachusetts farmers led by Daniel Shays. This rebellion highlighted the weaknesses of the Articles of Confederation, specifically its inability to raise an army and maintain order. Another weakness exposed was the government's limited power to address economic issues, such as printing worthless paper currency and resolving interstate trade battles.