Final answer:
Cluster C is characterized by anxious or fearful traits, insecurity, and inadequacy, and includes disorders like Avoidant, Dependent, and Obsessive-Compulsive Personality Disorders.
Step-by-step explanation:
The personality disorder cluster characterized by anxious or fearful traits, insecurity, and inadequacy is Cluster C. This cluster includes disorders like Avoidant Personality Disorder, Dependent Personality Disorder, and Obsessive-Compulsive Personality Disorder, which are often associated with high levels of anxiety and fearfulness. Personality disorders in this cluster are defined by patterns of chronic self-doubt, desires for control due to insecurity, and a need for reassurance or dependency on others.