Which theme would Geographers use to study the consequences of peoples' actions?

A. Projection
B. Location
C. Movement
D. Human Environment Interaction

The theme that geographers would use to study the consequences of people's actions is "D. Human Environment Interaction".

To arrive at this answer, it is important to understand what each of the given themes refer to in the context of geography:

A. Projection: This refers to the methods or techniques used to represent a three-dimensional object or Earth's surface on a two-dimensional surface, such as a map. It does not directly relate to studying the consequences of people's actions.

B. Location: This refers to the specific geographic position or coordinates of a particular place on Earth's surface. While it is an important theme in geography, it does not directly capture the study of people's actions and their consequences.

C. Movement: This theme refers to the study of how people, goods, and ideas move from one place to another, including the patterns and processes of movement. While the consequences of people's actions may be indirectly examined through studying movement, it is not the primary theme for understanding the consequences themselves.

D. Human Environment Interaction: This theme specifically focuses on the relationships and interactions between humans and their physical environment. It encompasses the study of how human activities modify and impact the environment, and how the environment, in turn, affects human behavior. Studying the consequences of people's actions aligns directly with this theme.

Therefore, the correct answer is D. Human Environment Interaction.