Question

how did the sinking of the lusitania in 1915 affect world war i?
the united states declared war on germany.
germany continued its policy of unrestricted submarine warfare.
germany restricted its submarine warfare in response to international outrage.
the united states began a policy of unrestricted submarine warfare.

Explanation:

The sinking of the Lusitania (a British ocean liner with U.S. citizens aboard) in 1915 sparked global outrage, especially in the U.S. To avoid drawing the U.S. into the war, Germany temporarily suspended unrestricted submarine warfare (which targeted civilian ships without warning) and restricted its submarine operations. The U.S. declared war later (1917), not immediately after the sinking; Germany resumed unrestricted warfare in 1917, not continued it in 1915; and the U.S. did not adopt unrestricted submarine warfare.

Answer:

C. Germany restricted its submarine warfare in response to international outrage.