What must happen before you can legally use a cell phone while driving if you are under 18?

The correct answer highlights that, in order to legally use a cell phone while driving if you're under 18, utilizing a hands-free device is necessary. This rule is put in place to promote safety by allowing young drivers to stay focused on the road while still being able to communicate. Hands-free devices facilitate the use of the cell phone without requiring the driver to hold the phone, thus minimizing distractions that could lead to accidents.

In contrast, other options suggest alternatives that do not comply with legal regulations. For instance, pulling over and parking may not always be practical or safe, and asking a passenger to handle the call does not eliminate the risk of distraction for the driver. Lastly, implying that young drivers cannot use a cell phone at all would not be accurate as the law permits usage with specific conditions, such as the requirement for a hands-free device. This reflects the balance between allowing communication and ensuring road safety, particularly for inexperienced drivers.