Why do earthquakes occur more frequently in a subduction zone than they do in the middle of a continent?

Because the zones of weakness are along the edge of the plates. Earthquakes occur when two plates meet.

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.