The name of the architectural achievement is C. the Forbidden City.
The Forbidden City is a large construction made of yellow roof tiles and red walls located in China's capital city, Beijing. As its name indicates, it is a micro-city. This precint is 961 meters long and 753 meters wide, and it consists of more than 90 palace compounds that include 98 buildings girdled by a ditch of 52 meters wide.
For almost 500 years, The Forbidden City was used as the emperor's home and a political and ceremonial center for China's government.