When researchers apply behavioral observation techniques to historical records in order to measure behaviors that occurred in the past, the measurement process is called ____

Depressed, or ____________(unpleasant), mood is the most common and obvious symptom of depression

Answer:

Which mental disorder is characterized by disturbances of thought, such as delusions and hallucinations?

A) Anxiety disorder B) Mood disorder C) Paranoid personality disorder D) Schizophrenia