For how many years is the Landtag in Saxony-Anhalt elected?

EDITORIAL LEARNING AID

Why is this answer correct?

The constitution of the state of Saxony-Anhalt sets a five-year electoral term for the Landtag. Three, four and six years do not apply to the state parliament.

Saxony-Anhalt: Landtag five years, local elections from 16.

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