I believe the answer is c
The phrase which has been often transposed to "Blood and Iron". His meaning was to gain the understanding that the unification of Germany will be brought about through the strength of the military forged in iron and the the blood spilled through warfare
Explanation : never listen to this nutter , he basically thinks that the only way to get to the point is by war and killing by building a larger arsenal
The effects of the Black Death were many and varied. Trade suffered for a time, and wars were temporarily abandoned. Many labourers died, which devastated families through lost means of survival and caused personal suffering; landowners who used labourers as tenant farmers were also affected.
I hope this is what you needed