During the antebellum period, what was the main product produced by both the north and the south

During the antebellum era, both the North and the South have been producing cotton and textiles. However, because the North has far more advantages than the south in terms of technological advancements, the North was able to produce more products by the end of the era such as guns, crops, machine parts and more. 

The answer to the question is a.