What is a functional region?
a. an area with at least one characteristic that distinguishes it from other areas
b. a region that is defined by individual human perceptions and feelings
c. an area that includes physically connected locations operating as a single unit
d. a region such as the rust belt of the united states

c. an área that includes physically connected lacations operating as a single unit.

An area that includes physically connected locations operating as a single unit ( C )

Explanation:

A functional region is said to be a region that is connected to areas around in the physical sense and its activities is been affected by these areas and also its activities affects these areas connected to it. example of such region is a major city surrounded by smaller towns around.

The activities of these smaller towns around contributes significantly to the well being of the Major city either economically or otherwise, example of the activities of the smaller towns are like agricultural items produced and supplied to the Major city for consumption while the Major city buys from the smaller towns and in turn generates some economic revenue for the towns.

example of a functional region in America is Atlanta.