The Invention of Machinery That Can Double the Amount of Gold

Multiple Choice

The invention of machinery that can double the amount of gold extracted from raw ore will likely lead mining companies to

A) raise the world price of gold to pay for the new machinery.
B) lower the world price of gold because any amount can now be produced more cheaply.
C) raise the world price of gold because miners' wages must double as their productivity doubles.
D) lower the world price of gold only if new mining companies are not allowed to enter the industry.