Final answer:
Paranoid Personality Disorder, Schizoid Personality Disorder, and Schizotypal Personality Disorder are all part of Cluster A, which is known for odd or eccentric behaviors and thinking.
Step-by-step explanation:
Paranoid Personality Disorder, Schizoid Personality Disorder, and Schizotypal Personality Disorder all belong to Cluster A. This cluster is characterized by odd, eccentric thinking or behavior and includes these three disorders as defined in the Diagnostic and Statistical Manual on Mental Disorders (DSM). It's important to note that while these disorders share similar characteristics, they are distinct diagnoses with their own specific criteria.
Cluster B includes personality disorders characterized by dramatic, overly emotional or unpredictable thinking or behavior, and Cluster C consists of anxious, fearful thinking or behavior. The subject of personality disorders is covered extensively in the field of psychology and specifically in the study of psychopathology.