Multiple choice technology programming languages

Given: 11. public static Iterator reverse(List list) { 12. Collections.reverse(list); 13. return list.iterator(); 14. } 15. public static void main(String[] args) { 16. List list = new ArrayList(); 17. list.add(” 1”); list.add(”2”); list.add(”3”); 18. for (Object obj: reverse(list)) 19. System.out.print(obj + “,”); 20. } ‘What is the result?

  1. 3,2, 1,

  2. 1, 2, 3,

  3. Compilation fails.

  4. The code runs with no output.

  5. An exception is thrown at runtime.
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C Correct answer
Explanation

The reverse() method is declared with a raw type 'List' instead of a generic 'List'. The enhanced for-loop expects an Iterable from the raw type, but when used with generics, this creates a type mismatch. The method signature needs generics or explicit casting to compile cleanly.

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