What was the major cause of the 2008 economic downturn in the united states?

The financial crisis of 2007–2008, also known as the global financial crisis and the 2008 financial crisis, is considered by many economists to have been the worst financial crisis since the Great Depression of the 1930s

A,) cause a & b are equal & both gives 180°

This country likely has a high total fertility rate (tfr).