posted by Courtney .
Which statements describe the geographic theme of regions?
a. Different types of regions have little or no effect upon each other.
b. Climate regions are defined by their average temperature and their political system.
c. Physical regions can be formed by mountains and oceans.
d. Cultural regions are limited to
e. Nations that are members of an economic region enjoy fewer tariffs than non-members.
f. Regions share one or more common characteristics.