Answer: Sara is using satellite imagery to study how forests are growing or shrinking as a result of human behavior.
Explanation: Gps is a positioning system and is more like a tracker.
GIS are computer-based tools used to store, visualize, analyze, and interpret geographic data.
Radar is used to help navigate ships in fog and airplanes in bad weather, and can detect a speeding car and track weather. Therefore C is the answer.