Which statement best describes the influence of World War I on submarine warfare?

• A. Submarines had no impact on WWI naval warfare.
• B. German U-boats demonstrated strategic impact of submarine warfare.
• C. Submarines were used primarily for cargo transport in WWI.
• D. Submarines were quickly outclassed by battleships in WWI.

Answer: (A)

World War I showed that submarines could reshape naval warfare by threatening shipping and warships from underwater. German U-boats carried out aggressive unrestricted submarine warfare, sinking a large portion of Allied merchant shipping and pressuring the Allies to change how they moved supplies and troops. This forced the development of new countermeasures—convoys, improved antisubmarine patrols, depth charges, sonar, and air reconnaissance—and altered strategic thinking about how to protect a nation's logistics at sea. The broader effect extended beyond tactics: submarine warfare helped influence international politics and contributed to the United States entering the war after several US ships were sunk. Consequently, submarines demonstrated a clear strategic impact in WWI naval warfare. The other statements don’t fit because submarines did have a significant impact, their primary role in WWI was not cargo transport, and they introduced a new kind of warfare rather than being quickly outclassed by battleships.