Dictatorship conflicts with a democratic constitution.

Political competition needs shared ground rules.

In a democracy, parties compete for support. They may propose different taxes, changes to laws or a new government. That disagreement belongs to the political process. Article 21 describes the role of parties in forming political opinion.

Seeking to establish a dictatorship differs from an ordinary programme of reform. It attacks the democratic ground rules themselves. Article 20 establishes Germany as a democratic federal state and places the source of state authority in the people. The question asks you to recognise that conflict.

The other three answers

The other three words do not describe the aim of establishing dictatorship.

The exam answer does not automatically ban a party.

The Federal Constitutional Court decides whether a party is unconstitutional under Article 21(2). A government, an authority or this study page cannot simply replace that decision. The legal determination follows a separate procedure.

Under the judgment of 17 January 2017, an anti-constitutional aim alone is insufficient for a party ban. There must also be planned action against the protected order and significant concrete indications that it could succeed. Remember both points: the catalogue answer is “unconstitutional”; an actual ban requires the additional legal conditions and a court decision.