You work as an application developer at Certkiller .com. Certkiller .com wants you to develop an application that handles passes for Certkiller .com’s parking lot. The application has to store and retrieve vehicle information using a vehicle identification number （VIN）.You need to use the correct code to ensure type-safety. What should you do？（）

• A、A
• B、B
• C、C
• D、D