Final answer:
The Harmonized System establishes classification numbers for importers and exporters, including the Harmonized Tariff Schedule (HTS) option (e). Another relevant classification system is the North American Industry Classification System (NAICS).
Step-by-step explanation:
The classification numbers that must be used by importers and exporters are established by the Harmonized System (HS). The HS is a standardized system for classifying goods in international trade. It is used by over 200 countries and covers approximately 98% of world trade.
One specific classification number system used by importers and exporters is the Harmonized Tariff Schedule (HTS). The HTS provides numerical codes for specific products, allowing customs officials to determine applicable tariffs, quotas, and regulations for those products.
Another relevant classification number system is the North American Industry Classification System (NAICS), which is used to classify businesses and industries in North America. While it does not establish import and export numbers directly, it provides a framework for organizing economic data on various sectors.