Which statement indicates an unfair trade practice?

Country X has trade agreements with many countries, including countries A, B, and C. Country X is a major exporter of iron, steel, and cheese. Its major imports include tuna, wheat, and electronic equipment. In 2011, Marlene Dairy Farm, one of the leading cheesemakers in country X, produced a record 70,000 tons of cheese. Marlene’s patented technology enabled it to produce cheese at the cost of $3 per ounce. But about 5% of the product was declared unfit for consumption. That rejected cheese had to be thrown away in keeping with state food waste management guidelines. The rest of the cheese was exported to three countries. Country X exported the cheese to country B at a price of $2 per ounce. Country C bought the cheese at $4 per ounce. Country X sold the cheese to country D for $4.5 per ounce. By 2013, Marlene’s was among the top five cheese exporters in the world.