Answer:
Alligator Carcasses
Explanation:
Scientists who dropped alligator carcasses onto the ocean floor to see how deep-sea creatures would respond were surprised to find the reptiles were devoured within hours. The experiment also led to the team discovering a new species of worm.
A and B is out because these undoubtedly are unique Chinese achievements. So is D. The Chinese are infamous for these things. Other achievements include gunpowder, fireworks, ect.
C is basically the answer because the chinese aren't the only race or country to do so. Many people have done it in the past before them and present in the terms of civilization. It isn't simply uniquely or originally from them.
According to my research, I found this:
The Fertile Crescent, name like this because of its crescent shape, is the region in the current Middle East where very ancient civilizations, like the Sumer and Ancient Egyptians proliferated, due to its excellent conditions for agriculture. Specially, due to the anual inundations of the rivers Nile, Euphrates and Tigris.
Moreover, these civilizations abovementioned started to specialize, to implement labor division in their socities, and were able to reach technological progress and to develop tools which made their crops even more profitable than before. Examples of these developments achieved were: writing, glass, the wheel, agriculture, and the use of irrigation.
Correct Answer: A large supply of immigrant labor (Irish and German laborers from the East, and primarily Chinese from the West.)