What is the main ingredient in a traditional risotto?

In traditional risotto, the main ingredient is rice, specifically a type known as arborio rice. This short-grain rice is favored for its high starch content, which is key to achieving the creamy texture that risotto is known for. When cooked with broth and stirred continuously, the starches are released, creating a rich, velvety dish.

The other ingredients listed, such as quinoa, barley, and pasta, do not carry the same properties that make risotto unique. Quinoa, while a nutritious grain, does not expand and develop creaminess in the same way rice does when prepared in this style. Barley could be used in some variations, but it is not a traditional base for risotto. Pasta is another staple of Italian cuisine, but its preparation and texture differ significantly from that of risotto, which is exclusively associated with rice. Thus, rice is the correct and traditional ingredient that defines the dish.