What Is the Ultimate Goal of Any Psychodiagnostic System

What is the ultimate goal of any psychodiagnostic system?

A) To determine the cheapest method in which mental health problems can be addressed by clinicians
B) To provide the clinician with tools that will allow the efficient and accurate labeling of clients
C) To help the psychologist determine which personality disorder a client has so that they know which medication should be prescribed
D) To understand the person's needs and resources and to facilitate the implementation of helpful therapeutic interventions