The correct option is C Enlargement of thyroid gland
Endemic goitre is a type of goitre that is associated with dietary iodine deficiency. Endemic goitre occurs when the prevalence of thyroid enlargement in the population of an area exceeds 10%. Endemic goiters occur in people within certain geographic areas who do not get enough iodine in their diet. Some inland areas, where soil and water lack in iodine compounds are endemic.