One of the following is not a valid statement: A) Fleming’s right hand rule is used to find out the direction of current in the conductor of a generator B) Fleming’s left hand rule is used to find out the direction of rotation of the armature of DC motor C) Ampere’s rule is used to find out the direction of lines of force around the wire carrying current D) Right hand thumb rule is used to find out the direction of counter current produced in the armature magnetic field