What is one requirement for a German QbA wine?

For a wine to be classified as QbA (Qualitätswein bestimmter Anbaugebiete) in Germany, it is essential that it shows the region it comes from. This designation indicates that the wine must be produced from grapes grown in one of the designated wine regions of Germany, ensuring a certain level of quality and geographical authenticity. The requirement for regional indication also highlights the importance of terroir in the quality and characteristic profile of German wines.

The other options provided do not align with the specific requirements for QbA classification. QbA wines must come from specific regions and adhere to the quality standards defined by the German wine regulations, whereas the alcohol percentage, aging requirements, and grape sourcing are governed by different criteria. Therefore, the correct answer underscores the significance of regional identification in the context of German wine regulations.