Answer:
a. It helped convince the United States to enter the war against Germany.
Step-by-step explanation:
The Zimmermann note was a telegram that was intercepted by the British. The note was written by Arthur Zimmermann and it was intended to reach the German ambassador to Mexico. The note gave instructions to the ambassador to approach the Mexican president and offer a secret alliance, Germany would provide military and financial support in exchange for Mexico to attack the US.
The Note was a push for the US to enter the war, In 1917 President Wilson abandoned the policy of neutrality and asked the Congress to declare war.