Vein deposits of gold and silver are formed by igneous intrusion, and intrusive igneous rocks account for sections of higher elevation. Given these facts, vein deposits of gold and silver are formed where among the following options:
- loose soil
 - aqueous solution
 - graptolites
 - tectonic plates coliding
 - higher elevations
 - mountain sources
 - flow of electrons
 - In sediment


 

     higher elevations    