Answer:
The answer for the question is option (D)-All of these
Allied forces faced all type of challenges during the world war two, from food to ammo. Every supplies that the allied forces needed at that time of war should have to cross the pacific oceans which were subjected to the difficulties of German's frequent attacks, climate of pacific ocean and distance that to be crossed.
German war planes gave a tough card to the supply ships of allied forces and the supplies failed to reach the troops on time. This situation increased the demand over supplies during the World War II.