Answer:
The correct answer is option "b."
Step-by-step explanation:
NAFTA is the abbreviation of the North American Free Trade Agreement and refers to the trade bloc between Canada, Mexico, and the United States of America.
The treaty does open borders for many industries by removing tariffs on all items who's country of origin is either Mexico, Canada, or the US. Furthermore, in terms of total GDP of member countries, NAFTA is considered the largest trading bloc on the planet.
Despite doing away with almost all of the tariffs, Canadian agricultural commodities such as dairy products are not included in the tariff elimination framework. Therefore, option "b" is incorrect since NAFTA does maintain certain restrictions on agricultural products.