A Number of Theories Have Been Proposed as to Why

question 19

Multiple Choice

A number of theories have been proposed as to why states developed in many parts of the world. They include

• A) the creation of irrigation.
• B) population growth, leading to competition, and warfare.
• C) the development of long distance trade routes.
• D) all of the above.

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Definitions:

Emissions-Threatening

Pertaining to substances or activities that pose a risk to air quality by releasing harmful pollutants.

Catalyst-Damaging

Pertaining to substances or conditions that can degrade or impair the function of a catalytic converter, which is an emissions control device in vehicles.

DTC

Diagnostic Trouble Codes, codes generated by a vehicle's onboard diagnostics system to indicate a problem.

SAE

Society of Automotive Engineers, an organization that sets standards for engineering professionals in various industries, especially automotive.