Which of the following diets excludes all animal-derived foods?

The diet that excludes all animal-derived foods is known as veganism. A vegan diet strictly eliminates all meat, poultry, fish, dairy products, eggs, and any other food derived from animals. This dietary approach is often chosen for various reasons including ethical concerns regarding animal welfare, environmental considerations, and health motivations.

In contrast, the other dietary choices include some animal-derived products. A lacto-vegetarian diet allows for dairy products but excludes meat and eggs, while an ovo-lacto-vegetarian diet includes both dairy and eggs. A flexitarian diet is primarily vegetarian but allows for occasional meat and fish, which further distinguishes it from a vegan approach. Thus, the correct choice highlights the comprehensive exclusion of all animal-derived foods characteristic of a vegan diet.