The correct answer is C. A weakness of Congress under the Articles of Confederation was that it could not collect taxes.
The Articles of Confederation constituted the first government document of the United States of America. They were approved by the Second Continental Congress on November 15, 1777, after several months of debate. It was a non-binding guideline until its ratification four years later, on March 1, 1781.
The Articles supported the Continental Army and allowed the thirteen states to form a united front before the European powers. However, as a tool to build an effective government in times of war, it was a failure. Congress could make decisions, but did not have the power to apply them. Perhaps, the biggest setback was the requirement of unanimous approval of the 13 States to modify the articles. At the same time, the most important power that Congress lacked was the power to collect taxes: it could only request money from the States. These, for their part, did not always comply with the demands and Congress did not have the necessary funds for its operation.