Question

Which was a major cause for the entry of the U.S into world war 1

Answer 1

The German announcement of submarine warfare, and the sinking of ships with American citizens on board was the primary cause of World War I. 

Answer 2

The major cause is the Germany was using submarines to sink down the American ships and killed all of the American soldiers, and that is why the U.S join the war and pay back... mark me brainlist please...