Which is the flag of the European Union?

EDITORIAL LEARNING AID

Why is this answer correct?

The flag of the European Union is blue and shows a circle of twelve golden stars; only Image 2 shows it. The other images show different flags, for example national flags or the German black-red-gold.

EU flag: blue with twelve golden stars.

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