I remember learning this, it should be A
The answer to the question above is to reduce air pollution in Mexico city.
In Mexico city, residents have been encouraged to use bicyles in order to reduce air pollution in the city. Using bicycle also helps reduce traffic congestion and decrease time spent on traveling to their destinations.
The term "Potlatch" came from the tribes of the Pacific Coast, though all tribes held celebrations. Overall, the answer that fits best is Pacific Coast.
I think that the only right option is c. Workers had easier jobs and shorter hours. It caused lower quality of production