Question

what was the most significant use of german submarines during world war i?
○ extending the expansion of the war
○ submarines were supposed to prevent a ground war in germany.
○ preventing the resupply of allied forces
○ reducing overall casualties

Explanation:

During World War I, German submarines (U - boats) were mainly used for unrestricted submarine warfare, with the key goal of attacking Allied supply ships to prevent the resupply of Allied Forces. The option "deferring the expansion of the war" is not accurate as submarines were used to engage in the war more actively. The idea that "submarines were supposed to prevent a ground war in Germany" is incorrect as their main role was not related to preventing a ground war on German soil. And "reducing overall casualties" is also wrong because submarine warfare actually caused many casualties and was not aimed at reducing them.

Answer:

C. preventing the resupply of Allied Forces