The event that occur on November 11, 1918 was that the Armistice ending the war was signed.
The armistice refers to a formal agreement of between conflicting nation which aims to stop fighting.
Therefore, the Option A is correct because the event that occur on November 11, 1918 was that the first American troops arrived in Europe.
Read more about Armistice
brainly.com/question/16363580