As soon as kublai khan, the mongol ruler who founded the yuan dynasty, chose a site for his capital city, he realized that he needed a hydraulic engineer. he found one in guo shoujing. what did kublai need guo to do for the city of beijing?

a. he needed guo to build a dam that would hold back the large lake near beijing, in case it flooded.

b.
he needed guo to design a way to route water to beijing, which had no natural waterways nearby.

c. he needed guo to design a palace that would be grander than all of the chinese emperors before him.

d. he needed guo to build windmills that could be used to ground large amounts of grain into flower.

The answer is B.  He needed Guo to design a way to route water to Beijing, which had no natural waterways nearby.

Explanation:

Guo Shoujing built a system of water irrigation and a canal for transportation in the Bejing area following orders from emperor Kublai Khan of the Yuan Dynasty.

B. He needed Guo to design a way to route water to Beijing, which had no natural waterways nearby.

Explanation:

Guo Shoujing was the engineer responsible for extending the Grand Canal to Dadu (now Beijing), which brought water to the city. Kublai Khan realized the importance of irrigation and water transportation, and wanted to design a way in which these problems could be addressed. Guo built a 30km channel from the Shenshan Mountain to Dadu. This extended the canal that linked the river systems of the Yangtze, the Huai and the Huang, bringing water and development to the city.