Which is not a carbohydrate - cereal or rice bread potato?

The answer is cereal.

Here's why:

* Rice, bread, and potato are all primarily composed of carbohydrates, specifically starches.

* Cereal is a broader term. While many cereals are made with grains like rice, oats, or wheat, and thus high in carbohydrates, there are also cereals that contain other ingredients like sugar, fruits, or nuts, making their carbohydrate content variable.

Therefore, while some cereals are high in carbohydrates, not all cereals are primarily made up of carbohydrates.