Description : Kelp is - (1) Sulphide mineral of iron (2) Partially decomposed vegetalion (3) Sea weed rich in iodine content (4) An aluminium silicate mineral
Last Answer : (3) Sea weed rich in iodine content Explanation: Kelps are large seaweeds (algae) belonging to the brown algae in the order Laminariales. Because of its high concentration of iodine, kelp has been used to treat goiter, an enlargement of the thyroid gland caused by a lack of iodine.