Which of these is a source of niacin?

Meat is a significant source of niacin, which is a B-vitamin important for energy metabolism and the maintenance of proper nervous system function. Niacin can be found in many animal products, particularly in lean meats, poultry, and fish, as they contain higher concentrations of this essential nutrient compared to plant-based sources.

While tofu, green vegetables, and sugary snacks may provide other nutrients, they do not offer substantial amounts of niacin. Tofu is a good source of protein and certain minerals, particularly for vegetarians, but it does not contain niacin in notable quantities. Green vegetables provide vitamins and minerals essential for health, but are not a prominent source of niacin. Sugary snacks, on the other hand, primarily offer empty calories with little nutritional value and lack niacin. Therefore, when considering dietary sources of niacin, lean meats clearly stand out as the most valuable option.