To make the code print 4, you need to ensure that the method in the Car class correctly overrides the abstract method in the Automobile class. The abstract method in the Automobile class is defined without parameters (abstract void wheels();), while the method in the Car class takes an int parameter (void wheels(int i)). This means that the method in the Car class does not override the abstract method in the Automobile class, and hence when ob.wheels() is called, it leads to a missing method implementation. By removing the parameter from the wheels method in the Car class, you ensure that it correctly overrides the abstract method in the Automobile class, fulfilling the requirement and allowing the code to print 4.