Answer:
C. the price effect would become a more significant consideration for each firm that makes automobiles.
Explanation:
The situation above is highly related to the topic about "supply" and "demand." If the nations of Germany, Japan and the U.S.A. prohibits the international trade in automobiles, this will result to a surplus of automobile goods within the country. Since these automobiles were meant to be sold abroad, the prohibition will lower its international demand. Such increase in supply will have a significant effect on the price of the automobiles. This is the reason why each firm should have to consider the situation's effect on the price of the automobiles and related goods.
So, this explains the answer.