What is the primary purpose of a driver's license?

Answer: B — To allow holders to drive legally on public roads

The primary purpose of a driver's license is to allow holders to drive legally on public roads. A driver's license confirms that the individual has met the required criteria, passed necessary tests, and understands the rules of the road. This ensures that drivers have the knowledge and skills to operate a vehicle safely, thereby promoting road safety and lawful driving practices. While a driver's license can also serve as a form of identification, its essential function is related to the legal permission to drive. Options that suggest it serves other purposes, like social security or travel arrangements, do not capture the main intent of issuing a driver's license.