garbage collector ?? pick odd one out

Question

Hi hello everyone 

pick odd one out ... i.e pick which is not true option
1. Garabage collector manages reclamation of unused memory
2.it deals with circular references 
3.you can be certain when an object will be reclaimed by GC
4.it disposes UN-referenced objects
------------> whats ur take on this with explanation please ... 

I am thinking of option 3 but not sure .. .. .. :)

Thank you