Thanks for the question +1 Kudos
. I was stuck between B and C and I have chosen C.
The testing case implemented on the mere users or the mere not users. It does not mention about the population. It says 100 people who did not use cocainne, the 5 will test positive and of the whom used cocaine 99% will test positive. So what if there are 1.000 cocaine users out of 1.000.000 people. It says a randomly chosen group it does not say 50 cocaine users and 50 not cocaine users. So it is unclear what is our big picture. If the case is above the percentages will be around 5% . But what if 500.000 out of 1.000.000 people(hypothetically) used cocaine than it would be around 52%.
When 100 people who have not used cocaine are tested for cocaine use, on average only 5 will test positive. By contrast, of every 100 people who have used cocaine 99 will test positive. Thus, when a randomly chosen group of people is tested for cocaine use, the vast majority of those who test positive will be people who have used cocaine.
A reasoning error in the argument is that the argument
(A) attempts to infer a value judgment from purely factual premises.
(B) attributes to every member of the population the properties of the average member of the population.
(C) fails to take into account what proportion of the population have used cocaine.
(D) ignores the fact that some cocaine users do not test positive.
(E) advocates testing people for cocaine use when there is no reason to suspect that they have used cocaine.
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