What is the primary feature of Mental Illness in an individual?

The primary feature of mental illness in an individual is a behavioral or psychological syndrome with present distress. This means that there is a noticeable pattern of behavior or psychological symptoms that cause distress to the individual experiencing them. Mental illness is characterized by a range of symptoms that impact a person's thoughts, emotions, and behavior, leading to distress or impairment in various areas of life. Therefore, option B is the correct choice as it accurately reflects the main characteristic of mental illness.

Options A, C, and D are not the primary features of mental illness. Option A refers to a pattern of coercive control involving economic abuse, which is more related to domestic violence dynamics. Option C refers to compulsive misuse of a substance, which is related to substance abuse disorders. Option D mentions a tool for assessing risk and intervention needs, which is more related to evaluation and intervention strategies rather than the defining feature of mental illness.