What caused many mountain men to become travel guides

a) the united states government placed limits the number of beaver trappers were allowed to kill

b)mountain men could make longer profits as guides than they could as trappers

c) the demand for fur decreased due to change in fashion and beavers were nearly extinct

d) they were constantly confronted by angry animal rights activists

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place

rain should be the answer.