Recall the Application About the Price of Wolfram During World

Recall the Application about the price of wolfram during World War II to answer the following question(s) .
-Recall the Application. Wolfram is an ore of tungsten from neutral Spain required for making armor plate and armor-piercing shell., When the World War II Allies, the United States, the UK and others, tried to buy up all of production to deny tungsten to the Axis, Germany and Italy, the program became very expensive because:

A) the war was very costly and neither side had much cash on hand.
B) when two groups try to buy up all of a product, price rises dramatically.
C) wolfram became very scarce driving up the price.
D) all of the above