Answer:
B. Germany sank several American ships and urged Mexico to invade America.
Step-by-step explanation:
Despite the general neutrality of the US during the beggining of World War One, the Germans make two mistakes that resulted in the entrance of the US into the first World War.
First, around 1917, the Germans attacked several American passenger and merchant ships off the coast of Great Britain.
Second, the British managed to intercept and decipher a telegram between German and Mexican officials. The telegram requested that if the US joined the fighting in WW1, then Mexico should ally with Germany, and attack the US.
WIth tensions already high, these actions urged President Woodrow Wilson, to official request a declaration of war against Germany.