Which war lasted from 1939 to 1945?

EDITORIAL LEARNING AID

Why is this answer correct?

The Second World War began in 1939 with the German attack on Poland and ended in 1945. The First World War lasted from 1914 to 1918, and the Vietnam War roughly from 1955 to 1975. The Gulf War took place in 1990/91.

1939 attack on Poland, 1945 capitulation.

This translation and explanation are editorial learning aids. The official German wording and answer key govern the examination.