Bunuel
To improve air quality, the city council of a metropolitan area is considering imposing a heavy fine on the use of diesel vehicles within city limits. The city's environmental officer claims that this fine will significantly reduce the level of air pollution in the city within one year.
Which of the following is an assumption on which the environmental officer's claim depends?
(A) The funding allocated to air quality monitoring in the city will not decrease from its current level.
(B) The number of diesel vehicles currently used within the city will not increase from its current level.
(C) The amount of industrial pollution in the city will not increase from its current level.
(D) The number of vehicles entering the city from nearby areas will not significantly increase over the next year.
(E) The overall traffic volume in the city will not increase from its current level.
To identify the assumption underlying the environmental officer's claim, we need to determine what must be true for the fine on diesel vehicles to effectively reduce air pollution.
The claim is that imposing a heavy fine on diesel vehicles will reduce air pollution within one year. This relies on the assumption that the fine will lead to fewer diesel vehicles operating within the city, and hence, lower levels of pollution from these vehicles.
Let's re-examine the options:
(A) The funding allocated to air quality monitoring in the city will not decrease from its current level.
- This relates to the ability to monitor air quality but does not directly affect the reduction in pollution itself.
(B) The number of diesel vehicles currently used within the city will not increase from its current level.
- This ensures that the current level of diesel vehicles does not increase, which is relevant but doesn't directly ensure the fine will reduce the number of diesel vehicles.
(C) The amount of industrial pollution in the city will not increase from its current level.
- This relates to industrial pollution, not vehicle pollution, and is less relevant to the claim about diesel vehicles.
(D) The number of vehicles entering the city from nearby areas will not significantly increase over the next year.
- This ensures that an influx of vehicles from outside the city does not counteract the fine's effect, which is relevant to maintaining lower pollution levels from diesel vehicles.
(E) The overall traffic volume in the city will not increase from its current level.
- This pertains to overall traffic volume, which includes non-diesel vehicles, and is less directly related to the specific impact of the fine on diesel vehicle use.
Among these, the assumption that directly supports the environmental officer's claim that the fine will reduce air pollution is:
(B) The number of diesel vehicles currently used within the city will not increase from its current level.
This assumption is crucial because if the number of diesel vehicles were to increase, the fine might not lead to a significant reduction in pollution, undermining the claim. It directly addresses the impact of the fine on the level of diesel vehicle usage, which is central to reducing pollution.
Thus, the correct answer is:
(B) The number of diesel vehicles currently used within the city will not increase from its current level.