Question

in 1915, the united states neutral stance was tested when germany asked mexico to attack the united states. sank the passenger ship lusitania. broke a deal to limit submarine warfare. signed the treaty of brest - litovsk with russia.

Explanation:

In 1915, Germany's sinking of the British - owned passenger ship Lusitania, which had American passengers on board, greatly tested the United States' neutral stance during World War I. The Zimmermann Telegram (asking Mexico to attack the US) was in 1917, the deal - breaking regarding submarine warfare happened later, and the Treaty of Brest - Litovsk was in 1918.

Answer:

B. sank the passenger ship Lusitania.