The right answer is “show the wealth of patrons”. In the Renaissance, a patron was a wealthy person who sponsored an artist for their work. For example, the Medici Family was one of those, they were a famous family from Florence who ruled and supported of the arts. Lorenzo the Magnificent, a famous member of it, is well-known for sponsoring Italian artists such as Michelangelo and Botticelli.
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.
These books are called Period pieces
National Grange of the Order of patrons of Husbandry