Is the north china plain east or west of the sichuan basin

The North China Plain is situated east from the Sichuan Basin. This wast plain is in the eastern part of the country. It is connected with the Sichuan Basin through the Yangtze River and the gorge that it has made, which represents a natural boundary between this two lowlands in China.

The answer is c, i, iii, and iv. this is because farming and mining deal with harvesting raw materials, construction work falls under manufacturing, and piloting a plane is a service. ii is wrong because making bread is using  raw materials to produce goods, which would fall under the secondary sector, not primary.