Answer:
the Appalachian Mountains
Explanation:
The Appalachian Mountains form a barrier and present a difficulty for those who want to travel the lands in an east-west direction. This hindered the expansion of British colonies in North American America towards the west, leaving that region decolonized for a long time, since the colonizers thought it best not to try to overcome the challenge, since the path was very incest, inhospitable and could present many dangers .
The country that faced a unity crisis due to having a large variety of ethnic groups was D.)Austria-Hungary.
<h3>Which groups were in Austria-Hungary?</h3>
Austria-Hungary was an empire that comprised of several ethnic groups including Serbs, Bosnians, Croats, Hungarians, and Austrians.
These groups wanted independence for themselves and this led to a lot of strife in the empire.
Find out more on Austria-Hungary at brainly.com/question/24213561
#SPJ1
The main advantage which the Germanic tribes had in their conflict against the Roman Empire at the time during the 3rdr and 5th century was that they were very motivated to defend their own lands which were invaded by the Romans. They also knew the terrain and felt comfortable being there.
