Which of the following styles has the lowest ABV?

Berliner Weisse is indeed known for having a lower alcohol by volume (ABV) compared to the other styles listed. Typically, this German-style wheat beer falls within the range of 2.5% to 4% ABV. It is often described as a refreshing, tart beer that is great for summer consumption.

In contrast, American Pale Ales usually have an ABV ranging from about 4.5% to 6.5%. Märzen, a traditional German lager often enjoyed during Oktoberfest, typically measures between 5.0% and 6.5%. Saisons can vary greatly but usually sit in the range of 5% to 7.5% ABV.

Thus, the Berliner Weisse's characteristic lower ABV makes it distinct among these styles, ideal for those seeking a lighter beer.