Deficit spending is government spending, in excess of revenue, of funds raised by borrowing rather than taxation. Kennedy supported it to increase growth and create more jobs.
The correct answer is - D. how to make iron.
The Zhou dynasty was one of the greatest dynasties of China, and among many achievements of their reign, the artisans of this dynasty managed to learn how to make iron. This was revolutionary for the Chinese people, and it was of great use in the agriculture after the tools for it started to come in iron version, and it made everything much easier, quicker, and more efficient.
Socialism is most likely related to communism.