Changes to the physical and biotic features of the Earth are called land and water transformations. Which of the following is an example of a water transformation?

A)Clearing land along an urban-growth boundary to allow a city to expand.
B)Constructing a dam along a river so that an expanding city may increase the availability of drinking water.
C)Clear-cutting a forest for the lumber needed to build the homes for an expanding city.
D)Clear-cutting a forest to make cropland to grow the food for an expanding city.