Which ballot paper would be valid in a Bundestag election? Based on the Federal Electoral Regulations (BWO), Annex 26

EDITORIAL LEARNING AID

Why is this answer correct?

A ballot paper is valid if the voter's will is clearly recognisable, for example through one cross each for the first and second vote; this is how ballot paper 1 is designed in the official model in Annex 26 of the Federal Electoral Regulations. Ballot papers without a marking, with several crosses for one vote or with additions that leave the will unclear are invalid.

Valid only if the voter's will is unmistakable on the ballot paper.

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