Where in North America Are Sinkholes Most Prevalent and Why

Where in North America are sinkholes most prevalent and why?

A) in Michigan, because outcrops of limestone are widespread and it is surrounded by the Great Lakes
B) in Washington state, because of all of the rain west of the Cascades
C) in metamorphic rocks of the Canadian Shield, because of all of the lakes
D) in Florida, because it is almost all limestone and has abundant groundwater
E) in Colorado, because layers of sedimentary rocks under the Great Plains bend up to the surface there