Thyroxine is

What does hypothyroidism induce in adults?

$A$ man has an $I.Q.$ equivalent to that of a boy $5$ years old; this is due to the deficiency of which hormone?

Which of the following endocrine glands stores its secretion in the extracellular space before releasing it into the blood?

Which disease in adults is characterized by the following symptoms: $1.$ Low metabolic rate,$2.$ Increase in body weight,$3.$ Water retention in tissues?

$A$ toxic agent present in food which interferes with thyroxine synthesis leads to the development of: