What causes mountain ranges to form?

Fold mountains occur on Collison zone plate boundaries, where two continental plates collide with each other, causing them to rise up

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.