Test students' ability to apply cost–benefit analysis and ethical reasoning to evaluate three policy options for reducing urban air pollution (e.g., congestion pricing, low-emission zones, subsidies/ incentives for electric vehicles or public transit). Require identification and quantification of direct and indirect costs and benefits (health, economic, environmental), use of discounting and sensitivity/uncertainty analysis, assessment of distributional effects and environmental justice implications, and a clear, evidence-based policy recommendation justified both economically and ethically. Appropriate for undergraduate interdisciplinary courses; medium difficulty.