Final answer:
Michelle is engaged in international trade by exporting her fashion designs, which positions her within the global marketplace driven by export sales.
Step-by-step explanation:
Michelle, an Italian fashion designer who exports her merchandise to the U.S., UK, and Brazil, is most likely involved in international trade. Engaging in this practice makes her part of the dynamic global marketplace that is characterized by a complex network of export sales spanning various countries and regions. Exporting goods and services is a crucial activity for many businesses seeking to expand their market reach beyond their national borders, cater to diverse consumer bases, and enhance their growth potential.