Question

an important environmental debate in the united states in 1900 was
whether to ban factories in cities.
whether to drill for oil offshore.
whether to use wilderness resources.
whether to use coal.

Explanation:

In 1900, a key environmental debate in the US was about using wilderness resources (like forests, lands for development/conservation). Banning factories in cities wasn't a 1900 environmental focus, offshore oil drilling was later, and coal use was already established. So the relevant option is about wilderness resources.

Answer:

whether to use wilderness resources.