Answer:
Decline in the education system.
A decline in the education system would have hindered the enlightenment, as the enlightenment itself is an age of progress is science and philosophy.
Explanation:
The answer is D, having to fight a two-front war.
The Schlieffen plan was the German strategy to quickly take out France so that they could focus all their troops on Russia.
Discrimination and being treated as second class citizens
