Which of the following actions is illegal regarding kratom for individuals under 21 years old?

Selling or distributing kratom to individuals under 21 years old is illegal, primarily because regulations often specify age restrictions on the sale of substances such as kratom. Many states have implemented laws that restrict access to certain products to protect younger populations from potential health risks associated with their use. The decision to restrict sales to minors aims to address concerns regarding substance safety and to promote responsible use among adults.

In contrast, the ability to purchase kratom with parental consent or use it for medicinal purposes may not necessarily violate regulations, provided that other legal requirements are met. Legal possession under adult supervision often allows younger individuals to have access to substances like kratom in safe environments, but does not allow for independent purchasing or distribution. Therefore, the action of selling or distributing kratom directly to individuals under 21 years old is specifically prohibited, making it the only clear illegal action in this context.