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OG Verbal Review #7

Expert replies
by rahulbhatia73 » Mon Aug 31, 2009 1:31 pm
A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The researcher conclused from this experiment that the immune system protects against mental illness as well as against physical disease.

The research's conclusion depends on which of the following assumptions?

A) High immune-system activity protects against mental illness better than normal immune-system activity does.
B) Mental illness is similar to physical illness in its effects on body systems.
C) People with high immune-system activity cannot develop mental illness.

D) Mental illness does not cause people's immune-system to decrease.
E) Physhological treatment of mental illness is not as effective as is medical treatment.
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Source: — Critical Reasoning |

by srivas » Mon Aug 31, 2009 6:41 pm
people with low immune system activity score low on tests of metal health.
Reseracher conclude that immune system protects against mental illness
.

from above statements we can say

Mental illness does not cause people's immune-system to decrease
Gmat710,, Hyd
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by heshamelaziry » Tue Sep 01, 2009 9:59 pm
A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity.

If we assume "A" to be a premises, it will make the conclusion valid.
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by ronaldo780 » Wed Sep 02, 2009 12:51 am
imo D. To draw the conclusion, the researcher must eliminate the alternate explanation that mental illness reduces the immune-system. Perhaps the people he/she tested were actually mentally-ill; this would explain both low immune system activity and low test scores.
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by heshamelaziry » Wed Sep 02, 2009 1:08 am
This is the second toughest one for the night. I know about eliminating alternate causes for the effect, but I can't mentally apply it here.
Maybe one of you guys can explain it further with different words....sorry for the trouble
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by vad3tha » Wed Sep 02, 2009 3:15 am
Its D. A seems right. But in the passage, the low level of immune system is compared with the high or normal one. So the measuring of higher or normal immune system is invalid.
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by kris77 » Sun May 15, 2016 4:08 pm
D seems to be the best choice here
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