The correct answer is B.Interchangeable parts were identical parts that could be exchanged for one another in manufacturing of goods.
Interchangeable parts revolutionized the American economy during this era. The ability to use identical parts for the same product increased the amount of manufactured goods that can be made by a company. Along with this, it also greatly decreased the time it took to create a manufactured good as well as decreased the price of what it took to made the good. This decrease in cost resulted in citizens saving money on these manufactured goods.