The steroid responsible for the balance of water and electrolytes in our body is:

1. insulin

2. melatonin

3. testosterone

4. aldosterone

(b) Aldosterone acts at the renal tubules stimulating the reabsorption of Na+ , water and excretion of K+ and phosphate ion. Thus, it helps in maintenance of electrolytes, body fluid volume, osmotic pressure and blood pressure.

Insulin is a peptide hormone, that plays an important role in maintaining the normal glucose levels.
Testosterone is the male sex hormone, stimulating male features like muscular growth, growth of facial and axial hair, aggressiveness, low pitch of voice, etc, and spermatogenesis.

Melatonin hormone has a very important role in regulating 24 hours (diurnal) rhythm of our body.