When were the National Socialists under Adolf Hitler in power in Germany?

EDITORIAL LEARNING AID

Why is this answer correct?

Hitler became Reich Chancellor on 30 January 1933; Nazi rule ended with the capitulation in May 1945. 1918 to 1923 were the crisis years of the Weimar Republic, not the Nazi period. 1945 marked the start of the occupation period, and 1989 saw the end of the SED dictatorship in the GDR.

Seizure of power in 1933, capitulation in 1945: twelve years of Nazi rule.

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