passing objects

If I instantiate an object in my application's main class, and then pass it to the constructor of another class which will need to use it, does the copy/assignment of the object to something local actually make another object?
Generic example below:
Class A {
ClassB B = new ClassB();
ClassC C = new ClassC(B);
}

Class C {
ClassB localB = null;
Class C (ClassB B) {
  localB = B;
}
}