A and E are the correct answers. Bulgaria and Albania are by Macedonia, meaning its by the old Yugoslavia, witch also means its more south of Europe. Croatia is part of what was Yugoslavia, making it too far south.
I believe your answer would be A- Farmers and urban dwellers.
Hope this helps. Correct me if I'm wrong.
Explanation:
Germany's condition of reduction of population is because of pandemic effect on global recolation.
Positive:There would not be much pandemics, diseases,& so on.
Negative: There would be an effect on economy, there'll be few or less workers,so on.(This would be a larger effect than the positives of course)
One reason of undergrowth is of jobless rate & bare utilisation anticipation.

I think this is the answer.
Check this site out it helped me A LOT!
https://en.wikipedia.org/wiki/European_migrant_crisis