The correct option is D PTH
Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low. It does this through its actions on the kidneys, bones and intestine.
Bones – parathyroid hormone stimulates the release of calcium from large calcium stores in the bones into the bloodstream.
ADH is antidiuretic hormone which helps in regulating water level in the body, GnRH is gonadotropin releasing hormone which helps in regulating reproductive axis, and LH is luteinizing hormone which helps in regulating sexual development in women.
So, the correct answer is option 'd'.