The correct answers are:
- rugged terrain;
- transpiration difficulties;
The Rocky Mountains are a vast mountain range, that is also very steep, and not the best for larger human settlements. Apart from the terrain being steep, it is also covered in dense forests, has lot of rocky parts, arid and semi arid areas, which are all not the most attractive locations for the people to move in. The type of the terrain also makes problems with the transportation, because the roads are not straight and on flat surfaces, but they are much more curly, covered with snow in the winter, rock debris is often falling on them, so the transportation is not the ideal.