Answer:
Mountains affect multiple aspects of human activity.
Explanation:
In the past, mountain ranges:
- were a barrier to expansion or migration
- served as a line of defense against invading armies
- provided a refuge during times of war
- provided sources of drinking water due to glacial melt
- enabled population groups to engage in the practice of Transhumance which took advantage of both high and lowland pastures
Today, mountains:
- offer exceptional tourism and sports options from hiking to mountain climbing to skiing
- mark natural national boundaries
- make the installation of infrastructure and the development of certain regions more difficult due to the extreme costliness of building roads through mountain ranges
