Why is $Thyroxine$ considered a hormone and not an enzyme?

Read the given statements $:$
$(A)$ Hypothyroidism during pregnancy causes defective development and maturation of the growing baby.
$(B)$ Thyroxine does not require a secondary messenger.
$(C)$ Thyroxine plays a major role in the regulation of Basal Metabolic Rate $(BMR)$.
$(D)$ Hypersecretion of thyroxine could cause immunodeficiency.
How many of the above statements are correct?

What are the effects of hypothyroidism (observed during pregnancy) on the development and maturation of a growing baby?

Exophthalmic goiter is caused by the hypersecretion of ..........

Hyperthyroidism causes which of the following diseases?

If a person consumes iodine,it will be stored in which of the following organs?