Consider the following class hierarchy:

public class Vehicle

{

   private String type;

   public Vehicle(String type)

   {

      this.type = type;

   }

   public String getType()

   {

      return type;

   }

}

public class LandVehicle extends Vehicle

{

   public LandVehicle(String type)

   {

      . . .

   }

}

public class Auto extends LandVehicle

{

   public Auto(String type)

   {

      . . .

   }

}

Which of the following code fragments is NOT valid in Java?