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
The msgjkljelokacamirwatapetfweyypunotcotcallos
I would say 30,000 cause all the next developments were from the 1860's forward and that is when huge growth happened, after 1860.
