Can anyone of you explain to me how come this answer comes up? I tried to read the explanation on the book so many times but still cannot get it yet. If possible, compare with sth more personal pls. Thx.
Question No.7 from Verbal Review:
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 concluded from this experiment that the immue system protects against mental illness as well as against physical disease.
The researcher's conclusion depends on which of the following assumptions?
Answer: Mental illness does not cause people's immune-system activity to decrease.
Question No.7 from Verbal Review:
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 concluded from this experiment that the immue system protects against mental illness as well as against physical disease.
The researcher's conclusion depends on which of the following assumptions?
Answer: Mental illness does not cause people's immune-system activity to decrease.
