Small amount of iodine is added to common salt so that
Occurrence of goitre is prevented
The correct option is C:
Explanation of the correct option :
Goitre is caused by the deficiency of iodine in the diet. Iodine is necessary for the synthesis of the thyroxine hormone. A small amount of iodine is added to common salt so that occurrence of goitre is prevented.
Explanation of the incorrect option:
Option A:
Edema is usually caused by: standing or sitting in the same position for too long. eating too much salty food, and being overweight.
Option B:
Common salt can be utilized without adding iodine.
Option D:
The kidney does not require iodine for being efficient in maintaining water balance.
Final answer: Small amount of iodine is added to common salt so that occurrence of goitre is prevented.