What is the effect of parathormone on the human body? 

Parathyroid hormone (PTH), also known as parathormone, is a hormone secreted by the parathyroid glands in response to low levels of calcium in the blood. Its main function is to increase blood calcium levels by stimulating the release of calcium from bone tissue into the bloodstream, increasing the absorption of calcium from the intestines, and decreasing the excretion of calcium by the kidneys. This is important for many physiological processes, such as muscle contraction, nerve function, and bone health. 

Therefore, the correct option is- Maintain blood calcium level.