![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
设有如下代码: 1. class Example{ 2. String str; 3. Example(){ 4. str= "example"; 5. } 6. Example(String s){ 7. str=s; 8. } 9. } 10. class Demo extends Example{ 11. } 12. public class Test{ 13. public void f () { 14. Example ex = new Example("Good"); 15. Demo d = new Demo("Good"); 16. } 17. } 以下哪行将导致错误( )。