Object which eligible to garbage collected

[Fisher Daniel]

Dear all, i have a question from a mock exam
Which of these statements are true?
Select 1 correct answer
a. Objects can explicitly be destroyed using the keyword delete
b. An object will be garbage collected immediately after the last referene to the reference to the object is removed
c. if object obj1 is accessible from obj2 and obj2 is accessible from obj1, than obj1 and obj2 are not eligible for garbage collection
d. Once an object has become eligible for garbage collection, it will remain eligible until it is destroyed
e. An bject can be finalized only once
The answer is e.
Why is answer c and d wrong?
daniel

[Valentin Crettaz]

c. if both objects are unreachable, then they may be garbage collected.
d. the finalize method may resurrect an object...
Here is a very interesting article about garbage collection. I think you should read it:
http://developer.java.sun.com/developer/technicalArticles/ALT/RefObj