Automobile-emission standards are enforced through annual inspection. ██ █████ ███████████ ████ ███ ██████ █████ ███████ ████ ███ ████████ █████ ████ █████ ███████ ████████ ███████ ███████ ███████ ███ ██████ ██ ███████ ██████████ ██ ███████ █████ █████ ███ ████ █████
The stimulus itself doesn’t provide an argument, but the question stem asks us why current automobile-emission enforcement may not be effective in controlling pollution. In other words, we need to weaken the conclusion that current enforcement is effective. The method of enforcement (i.e. the support for that conclusion) is that pollutant levels in exhaust are measured while a car is idling.
The conclusion we’re weakening assumes that cars emit similar or higher levels of pollutants while they’re idling than while they’re in motion. In other words, it assumes that a test while a car is idling will not find a significantly lower pollutant level than the car emits while being driven.
Which one of the following, ██ █████ ████ ████████ █████████ ████ ███████ ███████████ ██ ███████████████████ █████████ █████ ██ ███████████ ██ ███████████ ███████ █████████ ███████
As an emission-control ██████████ ██████████ ███ ███████ ███ ██████████ █████ ██ █████████████ ██████ █████████████ ████ ██████████
The testing devices ████ ████ ██ ████████████ ██████████ ██ ███████ █████████ ██████ ████ ██████████ █████████
The adjustments needed ██ ████ █ ███ ████ ███████ ████ ██ ██████ ████ ███ ███ ████ ████ ████ ██████ ██ ██████████ ████ ██████ ██ ███████ ███████
Most car owners ███ █████ █████████ ██ ████ ████ ████ █████ ████ ███ ██ ██████████ ████ ████████ ██████████
When emission standards ███ ████ ██ ██████████ ███ ████ ███ █████ █████