The following argument was taken from magazine and newspaper editorials and letters to the editor. In most instances the main conclusion must be rephrased to capture the full intent of the author. Write out what you interpret the main conclusion to be.
Most of the environmental problems facing us stem, at least in part, from the sheer number of Americans. The average American produces three quarters of a ton of garbage every year, consumes hundreds of gallons of gasoline, and uses large amounts of electricity (often from a nuclear power plant, coal burning, or a dam). The least painful way to protect the environment is to limit population growth.