Which of the following arguments was not raised in opposition to NAFTA? a. By creating a regional trading block, NAFTA would strengthen GATT's global trade liberalization achievements b. NAFTA would permit firms to take advantage of weaker environmental laws and low cost labor by locating plants in Mexico c. NAFTA would allow U.S. products and advertising to weaken the distinctive cultures and traditions of Canada and Mexico d. NAFTA would cause Mexican companies to suffer in competition a