## **Core Concept**
The question tests the understanding of defense mechanisms, specifically those employed by individuals to cope with or justify their behavior, in this case, alcoholism. Defense mechanisms are psychological strategies that people use to cope with stress, anxiety, or other uncomfortable emotions.

## **Why the Correct Answer is Right**
The phenomenon described, where a chronic alcoholic blames the family environment as a cause of his alcoholism, is an example of **externalization**. Externalization is a defense mechanism where an individual attributes the cause of their unacceptable thoughts, feelings, or behaviors to external factors, rather than accepting responsibility for their actions. This allows the individual to shift the blame away from themselves and avoid feelings of guilt or shame associated with their behavior.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is not provided, but typically, one would expect an incorrect defense mechanism here. For instance, if "denial" were an option, it would be incorrect because denial involves refusing to acknowledge the reality of a situation, not blaming external factors for one's behavior.
- **Option B:** Similarly, without the specific option, one can infer that any other defense mechanism not involving the attribution of one's behavior to external factors would be incorrect. For example, "projection" involves attributing one's unacceptable thoughts or behaviors to someone else, which is different from blaming external circumstances.
- **Option C:** Again, without specifics, one can deduce that any defense mechanism not accurately describing externalization would be incorrect.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that understanding defense mechanisms can provide insight into a patient's behavior and coping strategies. Externalization is particularly relevant in the context of substance abuse, as it can hinder an individual's willingness to accept treatment and work on personal issues contributing to their addiction.

## **Correct Answer:** D. Externalization