It is allowed to drive, drink even married for adolescents who are in the age of 18 in specific countries, while it is permitted in some countries. From my point of view, the ideal age has to remain stable, which is 18.
On the one hand, Due to the fact that, juveniles who are above 18 considered capable of managing themselves without anyone’s contribution in some countries. To illustrate, even though they can not control their gut feelings in some situations, which almost occures in everyone, they have a way of thinking, whether their way is beneficial or not. Furthermore, they have a good consideration about this topic, because I think the age of 18 is the most sensitive, crucial and fascinating years. In my opinion they need to enjoy their youth.
On the other hand, in terms of the juveniles who are 18 years old think like the way children do. For this reason, the countries such as United States, South Korea etc do not allow to have a freedom in those matters. For instance, United States does not let drink freely until the age of 21. However, even though drinking is strictly permitted in the USA, driving is allowed as soon as you turn to the age of 18. Additionally, though the age of 18 can seem young, teenagers in that age finished their growing such as height, and specific things in body biologically. I assume that sample refers to the maturity in that age in biological way.
In conclusion, everything has to be allowed for individuals who are 18 years old, as their way of thinking differs from children considerably.