What does the term "sin tax" refer to?

The term "sin tax" specifically refers to a tax designed to discourage certain behaviors that are considered harmful or undesirable by society, such as smoking, excessive drinking, or gambling. These taxes aim to reduce the consumption of these goods or activities, thereby promoting public health or moral standards. The additional revenue generated from sin taxes can also be used to fund programs related to health care, education, or substance abuse prevention.

In contrast, the other options do not accurately align with the definition of a sin tax. Taxing essential goods would typically be seen as regressive and is not intended to influence behavior. Luxury items and services may be subject to different types of taxes, but those taxes are not specifically aimed at modifying behavior in the same way that sin taxes are. Lastly, imposing a tax exclusively on the wealthy does not relate to the concept of a sin tax, which is focused on particular behaviors rather than income levels. Thus, the correct answer highlights the purpose and motivation behind sin taxes effectively.