The dragon backbone pump led to an increase in a. farming b. food surplus c. population size d. all of the above

Food Surplus

Explanation:

The dragon backbone pump was a device used in china during the Song dynasty, to pump the water into canals to irrigate crops and to collect fresh water from wells. The unique thing about this device that even a single man could operate it. It was in use for almost 300 years. It was portable and advanced irrigation and farming became much easier by allowing one person to do the job of many. It helped to produce surplus food.

no every country is held to the same degree as others just some member countries such as the usa and germany are more economically sound so the need to show there support to all others