When a psychologist compares the symptoms an individual is experiencing to the symptoms of various disorders to determine the specific disorder the individual has, the psychologist is concerned

a. treatment.
b. prognosis.
c. etiology.
d. diagnosis.

Diagnosis

Explanation:

The word diagnosis is very important and comes from the Greek word. Its meaning has been changed. In Greek mythology, the diagnosis means the discrimination between two things. The nature of diagnosis is mainly to identify the illness of a patient. A diagnosis make concluded the disorder of a patient. It is related to the identification of a disorder or disease.  

Thus here when a psychologist compares the symptoms a patient is related to the experience of another patient with a specific disorder, the psychologist is concerned with the diagnosis.

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