Final answer:
Germany developed and used U-boats during World War I as a strategic response to the British naval blockade. U-boats were effective in fighting against the British navy and were a cost-effective alternative to surface ships.
Step-by-step explanation:
Germany started to develop and use U-boats during World War I as a strategic response to the British naval blockade. The U-boats, or submarines, were effective in fighting against the mighty British navy because they could operate underwater and launch surprise attacks on enemy ships. U-boats were a cost-effective alternative to surface ships, as they did not require as many resources to build and maintain.
Learn more about Germany's use of U-boats during World War I