<s>[INST] context: - Given clinical features suggets the diagnosis of congenital hypothyroidism which can be caused d/t defect in thyroid. Hence option 4 is the answer. Cretinism: - Cretinism denotes physical & mental insufficiency secondary to congenital hypothyroidism. - Cretinism may be endemic, sporadic or familial & is twice as frequent in girls as in boys. - Iodination of salt has reduced incidence of cretinism in the United States and other countries. - The most common cause of neonatal hypothyroidism today is agenesis of thyroid, which occurs at rate of 1 in 4,000 newborns. - Symptoms of congenital hypothyroidism appear in early weeks of life and include sluggishness a large abdomen often with umbilical herniation impaired development of skeletal & central nervous system severe mental retardation protruding tongue low body temperature refractory anemia. stunted growth & characteristic facies - If thyroid hormone replacement therapy is not promptly provided, this results in mentally retarded dwarfs. [/INST] question: The parents of a 4-week-old girl complain that their baby is apathetic and sluggish. On physical examination, the child's abdomen is large and exhibits an umbilical hernia. The skin is pale and cold, and the temperature is 35degC (95degF). Which of the following provides a plausible explanation for the signs and symptoms of this child? | options: A: Cystic fibrosis B: Muscular dystrophy C: Parathyroid hyperplasia D: Thyroid agenesis | answer: D </s>