This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
True about Iodine deficiency disorder 
Select and explain. 
A. Exclusively found in Himalayan goitre bell, B. Only monitered by blood thyroid test, C. Includes only goitre, D. Goitre prevalence of >10% in an area is considered as endemicity
D: Goitre prevalence of >10% in an area is considered as endemicity
Answer: D: Goitre prevalence of >10% in an area is considered as endemicity 
Explanation: None