Question

Which sentence could be used as evidence to support an opinion piece about vehicle emissions and the environment?

Some well-meaning legislators have suggested banning certain vehicles that get very low gas mileage.
Many studies in the U.S. and elsewhere make it clear that such vehicles negatively affect the environment.
However, such legislation is a slippery slope and will inevitably lead to unintended consequences.
The government may start by banning gas guzzlers, but they'll end up by banning motor vehicles altogether.