Wow.. Alexander the Great.... I remember learning about him... Any ways to answer your question your answer would be possibly D.. if i am incorrect then I am truly sorry.
One is definitely tourism.
Explanation:
The factor that jeopardizes the ecosystem in Eastern Europe is the tourism industry. Individuals simply travel there and have a fabulous time yet they don't pay attention and leave beaches dirty. They are not dealing with nature and the administrations can't do much since sightseers leave a lot of money for the nations.
Answer:
If a spacecraft is in space for a long time, radiation is a problem. Designers must figure out a way to protect astronauts from the radiation.
Deforestation, that would be clearing the land leading to desertification
C. Americans had the right to expand their control across the continent.