Winning wars and gaining land
In total, the Black Death has killed about 450 million down to 350-370 million in the 14th century.
Hope that helped! :)
The WPB or War Production Board set the products that would be needed for war and they determined their pricing.
So I agree with you, the answer is A.
But I must admit I was a bit iffy between A and D but I'd still say that A is a better choice.
Hope this helped
