Critical Reasoning

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 immune
system protects against mental illness as well as
against physical disease.
The researcher's conclusion depends on which of the
following assumptions?

(A) High immune-system activity protects against
mental illness better than normal immunesystem
activity does.
(B) Mental illness is similar to physical disease 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 immunesystem
activity to decrease.
(E) Psychological treatment of mental illness is not
as effective as is medical treatment.

There is a great discussion of the question on the Veritas Prep Blog. One of our veteran instructors, Antony Ritz, not only breaks down the causation assumption in this question, but also points you to several other official questions that you can practice causation on!

here is the link: https://www.veritasprep.com/blog/2012/10 ... -part-iii/

Let me know if you have any questions after reading the blog post.

David