The 3rd one is the answer
It was built to keep the people of Berlin inside the country.
I could be wrong though.
The answer is option 3: A technique for making porcelain was perfected.
The art of making porcelain prospered in both periods. A lot of innovations were made in forms, glazes, decorative techniques methods of production and kiln technology.
During the Tang Dynasty, porcelain kilns were constructed all over the country and a type of vessel with molded decorations on it became very popular, which was made using an "upside down" and the coal was used as kiln fuel.
By the Song period, the manufacturing process was standardized (base-making, glazing, ingredient control, and temperature maintenance). In addition, the industry was divided into five types of kilns that had several features for glaze coloring and pattern design.
Europe sent manufactured goods and luxuries to North America. Europe also sent guns, cloth, iron, and beer to Africa in exchange for gold, ivory, spices and hardwood. The primary export from Africa to North America and the West Indies was enslaved people to work on colonial plantations and farms.
Sugar boosts independence
During those three centuries, sugar was by far the most important of the overseas commodities that accounted for a third of Europe's entire economy. As technologies got more efficient and diversified, adding molasses and rum to the plantation byproducts, sugar barons from St.
