Which of the following does not play any role in calcium balance in the human body?

1. Vitamin-D

2. Parathyroid hormone

3. Thyrocalcitonin

4. Thymosin

(d) Thymosin hormone has no role in regulation of blood calcium homeostasis. It plays a major role in the differentiation of T-lymphocytes, which provides cell mediated immunity. While, vitamin-D, thyrocalcitonin and parathyroid hormone plays a vital role in maintaining calcium homeostasis by regulating blood calcium levels.