Question

________________ is the study of how the natural world works, how our environment affects us, and how we affect our environment.
environmentalism
ecological footprint
ethics
environmental scien

Explanation:

The question describes a field that studies the natural world, environment - human interactions. Environmental Science focuses on understanding how the natural world functions, the impact of the environment on humans, and human impact on the environment. Environmentalism is more of a social movement, Ecological Footprint is a measurement tool, and Ethics deals with moral principles, so they don't fit the description.

Answer:

Environmental Science