Name the grape primarily used in the production of Barolo.

Nebbiolo is the grape primarily used in the production of Barolo. This variety is known for its high acidity, tannin levels, and aromatic complexity, which make it well-suited for creating age-worthy wines that are renowned for their depth and character. Barolo, often referred to as the "King of Wines," is produced in the Barolo wine region in Piedmont, Italy, where the unique terroir, including the soil composition and microclimate, further enhances the qualities of Nebbiolo.

The rich flavors associated with Nebbiolo in Barolo typically include cherry, rose, and truffle, along with earthy and spicy notes that emerge with aging. These characteristics are key to the wine's style and prestige, contributing to its robust reputation in the world of fine wine. The other grape varieties listed do not play a role in Barolo production, as Dolcetto, Merlot, and Cabernet Sauvignon are utilized in different wine expressions and regions, contributing distinct flavor profiles that do not align with the traditional and distinct style of Barolo.