Im going with automatic rifle because it gave them an higher advantage than to restock gun powered into their muskets..
The answer to this answer is A.
The National American Free Trade Agreement (NAFTA) had a purpose of supporting free and easier trade between other nations (specifically the US, Canada, and Mexico), which is very close to the details mentioned in this quote.
If you were to read the NAFTA, you would find this quote in Chapter 1, Article 102.
Grant and his Army of the Tennessee crossed the Mississippi River and drove the Confederate Army of Mississippi, led by Lt. Gen. John C. Pemberton, into the defensive lines surrounding the fortress city of Vicksburg, Mississippi.