Hint: Before telling the source of iodine we will first tell how iodine is used as sodium iodide in iodized salt for preventing the disease, goiter. Then we will also tell about the disease goiter. Thyroid is a gland found just underneath the Adam apple in your neck. The hormones, including the metabolism, secrete food into energy, help to control the body's functions. It also controls heart rate , breathing, digestion and mood.
Seaweeds from ribbons (sp. laminaries) contain iodine compounds that are extracted from the seawater by iodide ions. The iodine can be extracted from the algae (seaweed) by heating it to an ash, in air, with iodine.
So, the correct answer is “Option A”.
Additional Information: A condition which increases the thyroid size is known as a goiter. Anyone can have a goiter but women have a greater frequency. It sometimes affects the functioning of the thyroid. The main cause of goiters is iodine deficiency. Iodine is vital for the production of thyroid hormones in your thyroid. The thyroid works extra hard to make the thyroid hormone when you don't have enough iodine, which causes the gland to grow.
Note: The process of extracting iodine from the seaweed is by heating the seaweed into ash and then iodide is dissolved by boiling water from the residue and filtered from the solution, which is oxidized by hydrogen peroxide into iodine. At this stage, iodine will color the solution brown. Solvent extraction and evaporation of solvent can be carried out to isolate the iodine from this solution.