The correct answer is A) paying for the American Revolution.
In 1790, the United States was heavily in debt from paying for the American Revolution.
After the Revolutionary War, although victorious, the United States inherited a huge debt. Records show that by 1791, the US federal government debt was $77 million. The government had to issue federal bonds to face its financial compromises. The country owed so much money to France. The government also opted for the fastest way: to print more money. But this had a negative side. It led to hyperinflation.
The other options of the question were b) forming Congress, c) trading with Britain and d) forming the executive branch.