The correct answer is (d) iodine. Iodine is a trace element that is essential for human health. It is found in seafood, seaweed, and some vegetables. Iodine deficiency can cause a number of health problems, including goiter, hypothyroidism, and mental retardation. Iodine is administered in the form of iodized salt or potassium iodide.
Iron is an essential mineral that is found in hemoglobin, the protein that carries oxygen in the blood. Iron deficiency can cause anemia, which is a condition in which the body does not have enough healthy red blood cells. Iron is found in meat, poultry, fish, beans, and leafy green vegetables.
Vitamin A is a fat-soluble vitamin that is essential for vision, skin, and immune function. Vitamin A deficiency can cause night blindness, xerophthalmia, and keratomalacia. Vitamin A is found in animal products, such as liver, eggs, and milk, as well as in some fruits and vegetables, such as carrots, sweet potatoes, and dark leafy greens.
Fluorine is a mineral that is found in water and soil. Fluoride is added to drinking water in many countries to prevent tooth decay. Fluoride is also found in toothpaste and mouthwash. Fluoride deficiency can cause tooth decay.
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