For internal data processing, Dachverband Tanz Deutschland uses products and services of Microsoft Corporation (variants of the Microsoft 365 service) based in the USA. Microsoft has adopted the standard contractual clauses of the EU Commission in the license agreements of its products offered in the EU, but the USA is assessed by the European Court of Justice as a country with an insufficient level of data protection according to EU standards. There is still a risk that your data may be processed by U.S. courts, U.S. law enforcement agencies, and national security agencies in accordance with its laws for control and surveillance purposes, possibly without recourse. If you click "Yes", you consent according to Art. 49 para. 1, p.1., lit. a DSGVO that your personal data may be processed in the USA.
For more information about hosting of data at Microsoft 365 in data centers in Germany, see here:
https://www.microsoft.com/de-de/microsoft-365/microsoft-365-local-datacenter