How to set an bone to be the parent of an object?

Hey, I’m trying to make this object (the sphere) be bound to the the right arm of this simple rig, so when the “arm” moves up and down, so does the sphere. Does anyone know how to do this without making the sphere joined to the existing mesh?

select the object (the sphere), Shift-select the armature and verify you are in pose mode, then select the right arm bone if it’s not already, hit Ctrl+P (make parent) and choose -> Bone.

Thank you very much! Have a nice day.

Thank you!
I was just going to edit my post for adding:
at the bottom of the Tool panel (Undo panel) you can later choose whether you want to keep transormations or not.

Ok, thank you!