Which of the following is a common aroma from wine matured in a new oak barrel?

Wines matured in new oak barrels often develop a range of complex aromas due to the interaction between the wine and the wood. One of the most common aromas associated with this type of maturation is vanilla. This vanilla scent primarily comes from the natural compounds present in the oak wood, particularly vanillin, which is released during the toasting process of the barrels. The intensity of the vanilla aroma can vary depending on the type of oak used, the level of toasting, and the duration of maturation.

Other aromas listed, such as floral, metallic, and herbaceous, do not typically arise from maturation in new oak barrels. Floral aromas may be associated with certain grape varieties, while metallic and herbaceous notes often stem from factors unrelated to oak maturation. Thus, the characteristic vanilla aroma stands out as a hallmark of wines aged in new oak.