bschool83 wrote:
Since pollution-causing human activities can cause an increase in average global temperatures, the mild winters in the area could be a result of the high concentration of vehicle exhaust emitted in the region. However, some scientists argue that the mild winters are a result of the increased rate of conversion of commercial areas to industrial areas.
Which of the following, if true, strengthens the scientists' argument?
A) Although commercial property areas tend to emit significantly less pollution than industrial areas, they still emit more than the vehicles in the area on a given day.
B) Most of the people who work in commercial areas drive to work each day.
C) New strict laws in the area require buildings in the industrial areas to reduce their emissions by 60% in the next 5 years.
D) Vehicle exhaust is comprised largely of carbon monoxide, the same pollutant emitted by the industrial areas.
E) In response to consumer demand, exhaust levels per vehicle have steadily decreased in recent years.
bschool83:
I couldn't find this question in 1000 series. Could you please post the OA?
Or anyone who has seen this question before, could you please post the correct source of the question and OA.
IMO:
Ans: "A"
As nicely explained by Crick:
Pollution by Vehicles < Pollution by Commercial < Pollution by industrial areas.
If we assume Pollution by Vehicles to be constant,
Pollution by Vehicles + Pollution by Commercial < Pollution by Vehicles + Pollution by Industrial Areas
However, if we grade these components as:
Pollution by Vehicles in Commercial Area=100
Pollution by Commercial Area=200
Pollution by Vehicles in Industrial Area=0
Pollution by Industrial Area=250
The above expression fails. So, it all depends on the comparison between inflow of the vehicles between those two areas.
"E" gives a fact that's tempting but it is not good enough for comparison. What if the industries are not emitting pollution at all and the vehicles, despite lowered vehicular exhaust, is contributing to the pollution.
"D" can be ruled out because the volume of gas emitted is not shown. Both emits CO, agree, but what if industries are emitting 1 tonne of CO and the vehicles are emitting 10 tonnes of CO. Moreover, we don't even know what gases are actually in question. It may very well be SO2 that's the prime measuring factor for pollution.
Give and take, A sounds the best because changing a commercial area to an industrial area won't significantly change the number of vehicles in the area or the gas emitted by those vehicles.