You are presented with the question "what are vein deposits of gold and silver formed by?" and the following answer choices: 
- mines
 - tube
 - calcite
 - cracking
 - rocks
 - wind
 - granite
 - streams

Now knowing that vein deposits of gold and silver are formed by igneous intrusion and granite, on the other hand, is an intrusive igneous rock, choose the best answer.


 

       granite  