We form associations between two occurrences when

We form associations between two occurrences when they occur at the same time very often. 

For example, if it happens regularly (but by coincidence) that someone gets sick if a distant relative visits, people might start linking those events and believe that there is an correlation between them, or even a causation. 

This is often how superstitions arise. 

Esa es una abilidad se la ensenaron a sasuke su propia familia

The correct answer in this question  is option c. people in mountainous areas tend to be more isolated from other populations. this is the reason why their local languages do not spread. farming is their  one way of living among the highlanders.