Which food is an example of an incomplete protein?

An incomplete protein is defined as a protein that does not contain all nine of the essential amino acids that the body cannot produce on its own. Nuts are an example of an incomplete protein because they typically lack one or more of these essential amino acids, making them insufficient as a sole source of protein for the body.

In contrast, eggs and meat are complete proteins, meaning they include all essential amino acids. Tofu, derived from soybeans, is often considered a complete protein as well, providing all nine essential amino acids. Therefore, among the choices, nuts are correctly identified as an incomplete protein, as they do not fulfill the complete amino acid profile required for optimal nutrition.