The choices can be found elsewhere and as follows:
Individual countries had the right to determine if they were going to allow genetically modified crops to come into their country.
Individual countries had to consult the will of the people before they could ban genetically modified crops.
Individual countries were creating an unfair trade barrier if they banned genetically modified crops.
Individual countries had no say over the import of genetically modified crops from trading partners.
I think the correct answer is the first option. The WTO decision in 2006 related to genetically modified crops would be that individual countries had the right to determine if they were going to allow genetically modified crops to come into their country.