Assess students' recall of the major greenhouse gases (carbon dioxide, methane, nitrous oxide, water vapor, and fluorinated gases) and their primary natural and human sources—e.g., respiration and decomposition, wetlands, livestock and rice paddies, fertilizer application, fossil-fuel combustion, industrial processes, and refrigeration. Quiz focuses on identifying each gas and matching it to its main natural and anthropogenic sources with simple examples appropriate for grades 6–8.