Question

Deficiency of which leads to dental caries?

• A. Iron
• B. Copper
• C. Fluorine (Fluoride)
• D. Zinc

Hint:

Fluoride strengthens tooth enamel by forming acid resistant fluorapatite, so its deficiency raises the risk of cavities.

Answer 1

The Correct Option is C

Step 1: Recall what protects teeth from decay.
Dental caries, commonly called tooth decay or cavities, happens when acids produced by mouth bacteria dissolve the hard enamel covering the teeth. The mineral that strengthens enamel and makes it resistant to this acid attack is fluorine, usually present in the body as fluoride.

Step 2: Explain the role of fluoride in teeth.
Fluoride combines with the calcium and phosphate in tooth enamel to form a harder compound called fluorapatite. Fluorapatite resists acid dissolution far better than the enamel's normal mineral form. This is exactly why fluoride is added to toothpaste and, in many places, to drinking water. When the diet or water supply lacks enough fluoride, enamel stays weaker and more prone to decay, so a fluoride deficiency raises the risk of dental caries.

Step 3: Check why the other minerals do not fit.
Iron deficiency mainly causes anaemia, since iron is needed to build haemoglobin in red blood cells; it has no direct link to enamel strength.
Copper is needed for enzymes involved in connective tissue and iron metabolism, and its deficiency causes issues like anaemia and bone abnormalities, not specifically tooth decay.
Zinc deficiency affects wound healing, immunity, and growth, but it is not the mineral primarily tied to cavity formation.

Step 4: Final answer.
Among the four options, only a lack of fluorine (fluoride) is directly linked to weaker enamel and dental caries.
\[ \boxed{\text{Fluorine (Fluoride)}} \]