Please note what it says on the title page of this forum
We're all here to learn, so when responding to others, please focus on helping them discover their own solutions, instead of simply providing answers.
It does not help the OP to be told the answer like that; it reduces the educational value of the discussion. Please don't be annoyed, but I have pulled rank and removed part of your pots.
It might be worth reading about overloading in the Java Language Specification, but it is by no means easy to read. You may need to go on to §15.12.2.
In a case of overloading, the compiler chooses the method whose parameter type is more specific. A null might be an Object or an array of Objects. An array of Objects is more specific; an array of Objects is an Object but an Object is (usually) not an array of objects. So Object is more specific and that is chosen by preference.
This shows a pitfall of overloading; it is not obvious to the reader which method is chosen.