B)
Source: http://www.loc.gov/teachers/classroommaterials/presentationsandactivities/presentations/timeline/civilwar/recontwo/
This site should help.
http://regentsprep.org/regents/core/questions/questions.cfm?Course=ushg&TopicCode=3c
With war, every country is afraid. They're afraid of possibly being ambushed, becoming in dept, and many other reasons. So by remaining neutral they can sit back and not have to worry about being attacked by any country that's fighting. But that's not always the case now and days. Hope I answered your question correctly.
Answer:
the desire to spread European culture
