Which kind of problem could have an impact on the global economy? A. Melting of polar ice caps
B. Sand erosion along a beach
C. Flooding of a river
D. Habitat loss in a forest

flooding of a river

Explanation:

Many cities are located along rivers and could cause businesses to shut down

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

geologic time scale (for gradpoint) =)