What is one reason that China has lost much cropland since about 1960? 

A)  population decline 
B)  war 
C)  the adoption of a one-child policy 
D)  industrialization

China's industrialization has led to rapid urbanization and development of infrastructure, which has resulted in the loss of cropland to make way for factories, buildings, and roads. Since 1960, the country's urban population has increased significantly, leading to an increased demand for urban infrastructure and services, which has come at the expense of agricultural land.