Why did farmers in the 1930s often fall behind on their tax payments?
they had very little money.
they needed equipment and seed.
they had to pay high taxes.
they were not required to pay taxes

The main reason why farmers were unable to pay their tax payments was mainly because they had very little money. In the 1930s, the bi recession was finally moving towards an end but the group of people who still drastically felt it were farmers who couldn't afford much in their lives at the times and because of which they couldn't pay their tax payments.

One reason why farmers in the 1930s often fell behind on their tax payments was because "They had very little money," since demand for crops during this time in the US was especially low. 

I’m pretty sure it’s 4, you can check on the calculator