Read following statements w.r.t. thyroid glands.
(i) It secretes a steroid hormone called thyrocalcitonin
(ii) Helps in maintaining water and electrolyte balance
(iii) Controls the metabolism of carbohydrates, proteins and fats with the help of thyroxine
(iv) Regulates basal metabolic rate (BMR)
(v) Support the process of red blood cell formation 

How many of the above statements are correct?