Electing a Chancellor does not elect every minister.
In the Chancellor election, MPs vote on the person who will lead the government. They do not simultaneously fill every ministerial post. Further stages of forming a government have their own constitutional rules.
Parliament continues to scrutinise the resulting government. A governing majority links the institutions politically but does not make them the same institution.
The other three answers
The three other answers concern genuine parliamentary functions.
draft laws.
Bills may be introduced from within the Bundestag. Parliamentary legislative work is therefore a valid function.
control the federal government.
The Bundestag scrutinises the federal government, including through questions, debates and committee work.
elect the Federal Chancellor.
Article 63 expressly assigns election of the Chancellor to the Bundestag.
Political negotiations and legal appointment are different.
Parties often negotiate coalitions and the allocation of ministries. These agreements do not replace the required election and appointment procedures.
Ministers often also hold seats in parliament. This does not change which institution performs each function. Office, parliamentary mandate and procedural role must be considered separately.
Articles 62–64 · Basic Law ↗Parliament elects Chancellor—Chancellor proposes ministers—President appoints.
The question asks for the step parliament does not itself perform.
Three words for this question
- das Bundeskabinettfederal cabinet
- The Chancellor and federal ministers together.
- ernennento appoint
- To formally install a person in office.
- kontrollierento scrutinise
- To examine government activity and hold it to account.