Answer: A private carrier
Step-by-step explanation:
Private carrier refers to those firms or business that have their own transportation vehicles which transport the good that they produce. Their service is not to transport goods hence they don't provide their transportation services to other companies which means their transport vehicles are not for hire.
For example a coal mine that has its own trucks or trains to transport their coal to where it is further processed daily, their primary business is not to transport coal but they extract coal then have it transported to their other site for further processing, those trucks or trains are private carriers. Since this is a daily activity it may be expensive for a coal company to hire trains or trucks everyday to transport their good but may be a low cost if they have their own transport vehicles for their everyday transportation.