The correct answer is - a. True.
Even though it may seem strange that the environmental scientists partially have their focus on the natural resources and their use, it actually doesn't have to come as a surprise considering the negative effect that the usage of the natural resources has on the environment.
The natural resources like the oil, natural gas, coal, are very damaging to the environment. The environmental scientists are trying to find solutions as to how to minimize and stop their usage, and in general they are trying to focus the societies more towards the renewable resources as they are much more environment friendly.