Follow-up case c) cannot be verified because there are no sales or production if the overdue period of 3 months, the follow-up is considered to be terminated and, though the end result tracking.
c) if the results can not be verified. Since no production or sales if more than three-month period shall be deemed to be the end result. And be deemed as a follow-up ended.
C) case follow-up cannot check, as there is no production or sell if the overdue period 3 months. Consider the follow-up is off. And deemed that follow-up ended.