In 1988, 50 people with emotional disturbances
underwent hypnosis to be cured of their mood
swings. A followup survey in 1993 revealed that
five had fairly stable emotional conditions at the
time of the survey. These five subjects can
therefore serve as models of the types of
people for whom hypnosis is likely to be
successful.
Which of the following, if true, casts the most
doubt on the suitability of those five subjects as
models in the sense described?
(A) The five subjects have very different
personalities and backgrounds.
(B) Since 1988, the five subjects have
experienced dramatic mood swings
interspersed with periods of relative
stability.
(C) Those people who were still suffering from
unstable emotional conditions at the time
of the 1993 survey had shown no
improvement since 1988.
(D) Many psychologists are less concerned
about a patient’s mood swings than about
the patient’s willingness to express his or
her problems and fears.
(E) The emotional condition of most of the 45
subjects who were still unstable at the
time of the 1993 survey had actually
worsened since 1988
I agree with B as well. Here's why.
Brief Analysis: The argument is that 5 people were stable at the TIME of the survey, which in turn makes a claim that they should be able to serve as models for the types of people that hypnosis will be successful for.
Reasoning for Answer: B indicates that the subjects have gone through multiple mood swings followed by periods of stability. Choosing them puts the argument in jeopardy because one day they could be fine, the next day they could be emotionally unstable again, which definitely wouldn't make these people good models