Overriding i overloading

Following code fragment is given (Java 5): 1: class Human { 2: Human getIt() { 3: return this; 4: } 5: } 6: 7: class Worker extends Human { 8: // insert a single method here 9: } Which of the following methods would compile if inserted at line 8
Human getIt() { return this; } Worker getIt() { return this; } Object getIt() { return this; } int getIt() { return 1; } int getIt(int x) { return 1; } Object getIt(int x) { return this; }