Spanish reading comprehension

Mary just sent out invitations to her wedding last week the invitations were so heavy that she put more than just one stamp on each envelope she used 255 stamps and mailed out 85 invitations and see you as an equal amount of stamps on each envelope

Question 2 multiple choice worth 2 points) which of the following means "she has just arrived at school"?

—¿ es tu celebración favorita? —mi celebración favorita es el cumpleaños de mis hijos.