What characteristic does Merlot add when blended with Cabernet Sauvignon?

The characteristic that Merlot adds when blended with Cabernet Sauvignon is softness and body. Merlot is known for its smoother tannins and rounded mouthfeel, which can soften the more structured and tannic qualities of Cabernet Sauvignon. This blending technique helps create a more approachable wine, balancing the intensity of Cabernet with Merlot's fruit-forward nature and velvety texture. The result is a wine that possesses both richness and smoothness, making it enjoyable to a wider audience while still retaining the complexity associated with Cabernet Sauvignon.

In this context, while increased acidity, herbaceousness, and fruity aromas may be associated with various other varietals and blends, they do not directly exemplify the primary attributes that Merlot contributes to the partnership with Cabernet Sauvignon. The focus here is on the complementary qualities that enhance the overall wine experience.