The correct answer is - 4. A formal region is established by administrative forces or physical characteristics, and a vernacular region has no formal boundaries.
The formal regions are regions that have boundaries set by the administrative forces or as a result of physical characteristics, and in this type of region very often there's people from multiple ethnicity, religions, cultures, races.
The vernacular regions, on the other hand, are regions that are not officially separated by other regions, but instead, are regions where the people share one or more common physical or cultural trait.
