The correct answer is 4. The industrial and manufacturing areas thrived.
The Union's economic structure thrived during the Civil War due to the amount of resources needed by Union troops. The development of guns, ammunition, warships, clothes, and other materials for the troops were all reliant on industrialization and manufacturing. The demand for these types of goods encouraged business owners to make these products at a rapid pace so that they could generate a large profit. This is why industry and manufacturing thrive during the Civil War.
C) allowing free and fair elections
D before the Crusades trade was literally nonexistent between them and after it brought new technology and products such as silk and food etc.
