The best description of a key challenge faced by the early American republic after the Revolutionary War is:
The creation of a strong central government to address issues of state sovereignty and weak federal authority.
After the Revolutionary War, the Articles of Confederation created a weak federal government, which struggled to manage economic issues, interstate disputes, and foreign relations. The need for a stronger central government eventually led to the Constitutional Convention in 1787 and the drafting of the U.S. Constitution.