In 1986, the city of Los Diablos had 20 days on which air pollution reached unhealthful amounts and a smog alert was put into effect. In early 1987, new air pollution control measures were enacted, but the city had smog alerts on 31 days that year and on 39 days the following year. In 1989, however, the number of smog alerts in Los Diablos dropped to sixteen. The main air pollutants in Los Diablos are ozone and carbon monoxide, and since 1986 the levels of both have been monitored by gas spectrography
Which of the following statements, assuming that each is true, would be LEAST helpful in explaining the air pollution levels in Los Diablos between 1986 and 1989?
(A) The 1987 air pollution control measures enacted in Los Diablos were put into effect in November of 1988.
(B) In December of 1988 a new and far more accurate gas spectrometer was invented.
(C) In February of 1989, the Pollution Control Board of Los Diablos revised the scale used to determine the amount of air pollution considered unhealthful.
(D) In 1988 the mayor of Los Diablos was found to have accepted large campaign donations from local industries and to have exempted those same industries from air pollution control measures.
(E) Excess ozone and carbon monoxide require a minimum of two years to break down naturally in the atmosphere above a given area.
answer i think is B
i guess the ans is “C” for if they revised the sacle the eariler values or which they considerd were wrong or not acurate
gmat tema pls expalin i guess even ” a” is right so pls explain
D is the answer.
A, B, C and E help in explaining the results provided in argument.
Let us see how each argument does/doesn’t help in ‘explaining the results’
A – The pollution-control actually started in Late ’88. Yes! That can explain the results. (enact- To make into law)
B – The gas spectrometer that was being used until Late ’88 was INaccurate. Yes.
C – A revised scale would mean that results will change.
E – Yes
D – if this were true, the numbers in 88 should have been low. But, in fact, they were the highest.
HTH
~magnus1
A
B
I think it’s d. If the mayor had accepted bribes and exempted a certain industry from the pollution control measures in 1988, it still wouldn’t explain whythe rates were also higher in 1987, when there hadn’t been a bribe.