D) Northern industries, such as manufacturing and shipping, benefited from the cheap southern materials and exporting their own goods.
Explanation:
Since the early colonial period the north created mainly a manufacturing economy. This had to do with the natural resources they had available, but also the weather conditions in the area. The cold temperatures made large-scale plantations impossible. The north had an abundance of timber and began to exploit the resource. They also established important ports for sea trade which continued to be used during the 1800s and beyond. Eventually they created an industrialized economy that manufactured goods based on raw materials from the south, and exported the finished products to the rest of the country and even Europe.
South Vietnam was fighting off the Communist North and Eisenhower used the excuse of "stopping the spread of Communism" to fund and support South Vietnam.
