Which is a formal region?

(Points : 1)

The state of Illinois


The Chicago metropolitan area


The historic neighborhoods in Boston


The trade route along the Mississippi River

Verified Answer :

formal means official or recognized 

so the best answer would be the state of Illinois, the others are general areas

AL2006


The State of Illinois is a formal region, with a sharply defined boundary.
In principle, with careful enough measurement, you can always find
exactly where any place on its boundary is, and you can stand there
with one foot inside Illinois and one foot outside of it.  I have done this
many times.