Choose the correct alternative from the following : - Assertion (A) : Goitre is a common disease in mountainous regions. Reason (R) : The diet of the people in mountains lacks iodine content.
Answer: A. Both A and R are true and R is the correct explanation of A.
Goitre is commonly caused in mountainous regions because goitre is caused by deficiency of iodine and diet in mountainous areas lacks iodine.