The conclusion of the argument is: "when such glasses are worn, it is because the wearer has a tendency to be depressed or hypochondriacal."
Why? Psychological tests given in Britain to hospitals patients admitted for physical complaints like heart pain and digestive distress confirmed such a relationship.
We are looking for the answer choice that either strengthens or does nothing.
Answer choice (B) states: "Even a depressed or hypochondriacal person can have valid medical complaints, so a doctor should perform all the usual objective tests in diagnosing such persons."
The argument never mentions doctors performing objective tests. A doctor having to perform all the usual objective tests in diagnosing such persons has no effect on the argument that sunglasses are worn because the wearer has a tendency to be depressed or hypochondriacal. This answer choice does nothing to the argument, and therefore, it is our answer.
Hope that clears thing up! Please let is know if you have any other questions.
