Iodine is an essential mineral that the body needs for proper thyroid function. The best source of iodine, as per the correct answer option 2, is beans. Beans, including kidney beans, black beans, and navy beans, are a good source of iodine. They are also high in fiber and protein, making them a healthy addition to any diet. Algae (option 1) can also be a good source of iodine, especially types like kelp and seaweed. However, beans generally contain higher levels of iodine compared to algae. Radish (option 3) and wheat (option 4) do not contain significant amounts of iodine, so they are not the best sources. It`s important to remember that if you have specific iodine needs or concerns, it is always a good idea to consult with a healthcare professional.