Some people oppose testing of employees for use of illegal

Question

Some people oppose testing of employees for use of illegal drugs on the ground that the tests sometimes produce false results. These fears are without basis. The newest tests can detect over ninety-nine percent of the cases in which a person has used one of the most common illegal drugs at any time during the previous 48 hours.

which of the following, if true, would most weaken the argument above?

A) The best drug tests available today return a significant number of positive results even when the person has not used drugs.

B) The best drug test available today cannot reliably identify every form of illegal drug that a person might have used.

C) The best drug tests available today cannot identify an illegal drug if the subject took that drug more than 48 hours prior to the test.

D) An employee who occasionally uses an illegal drug may still be a valuable worker.

E) Some employers still continue to use older and less reliable drugs tests.

Please answer with explaination

cbrf3 · Answer

By POE it comes down to C.......somehow I was leaning towards A but it looks like A strengthens the argument.......!!

singh_satya · Answer

I will go with A. what is OA

Satya

SmashingGrace · Answer

I think that the answer is A.

The argument in the paragraph is in support of drug testing. In order to weaken the argument, we need to oppose the drug testing on the basis of accuracy of the tests.

I believe that A does the best job in this case.

praveen_rao7 · Answer

A would be my choice too. Where did this problem come from?

GoalStanford · Answer

A.

B and C explain about how they can not identify illegal drugs but we should look for wrongly identifying possibilities. A provides that.

Paul · Answer

How can it be C? A it is.

X says that tests sometimes produce false results. 
Author says that these fears are without basis.

Hence, author wants to provide support for the accuracy of those tests. A says that those tests are often times inaccurate and directly attacks the author's claim and weakens the argument. Whether the drug is accurate or not when drug was consumed in the 48 hours prior to testing is out of scope. We are  only  interested in the accuracy of the test if drug was consumed  in the last 48 hours .

becoolja · Answer

Nong Chung Tee Na Ruk!! How can you get this question? From Saguan? Let me think and I will answer next time na ja. What's the meaning of your name..CHUNG :-)

ie ie

chung · Answer

hi guy

yes the OA is A

At first, i didn't read carefully ;so, i falled into the trap ( i chose C). So, thank you to clarify my doubt in this question, expecially paul!. your explanation is so clear

Some people oppose testing of employees for use of illegal

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