The Darwin's theory of evolution states that the organisms evolve through the process of the natural selection of the favorable genetic variations gradually over time. Through this process of the evolution, new species are developed over time. A single population may give rise to different species. These newly evolved species share similarities will each other as they have the same ancestor.
The EPA is an independent agency formed for environmental protection. Hence the statement The Clean Air Act would be a reason for the Environmental Protection Agency (EPA) to regulate car emissions is true.
Car emissions are very harmful for all the living organisms in an environment.