强因果题

wendybao

A reasearcher 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 reasearcher concluded from this experiment that the immune system protects against mental illness as well as against physical disease.

The researcher's conclusion would be most seriously weakened if it were true that

A) there was a one-year delay between the completion of a pilot study for the experiment and the initiation of the experiment itself.

B) people's level of immune-system activity are not affected by their use of medication.

C) a few peopld with high immune-systme activity had scores on the test of mental health that were similar to the scores of people who had normal immune-system activity.

D) people who have low immune-system activity tend to contract more viral infections than do people with normal or high immune-system activity.

E) high levels of stress first cause mental illness and then cause decreased immune-system activity in normal individuals.

答案选E.老师说这题是强因果题，怎么看是强因果（强加因果关系）啊？

wendybao

Pls pls pls help!

wendybao

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