Which of the following are not the effects of parathyroid hormone?

(a) Stimulates the process of bone resorption.

(b) Decreases ${\mathrm{Ca}}^{2+}$ level in blood.

(c) Reabsorption of ${\mathrm{Ca}}^{2+}$ by renal tubules.

(d) Decreases the absorption of ${\mathrm{Ca}}^{2+}$ from digested food.

(e) Increases metabolism of carbohydrates.

Choose the most appropriate answer from the options given below:

PTH, also known as parathormone, is made by the parathyroid glands. PTH is directly involved in the functioning of bones, kidneys, and the small intestine.

• In the bones, PTH stimulates the release of calcium in an indirect process through osteoclasts which ultimately leads to resorption of the bones.
• Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low.
• In the kidney, parathyroid hormone blocks the reabsorption of phosphate in the proximal tubule while promoting calcium reabsorption in the ascending loop of Henle, distal tubule, and collecting tubule. 
• PTH indirectly increases calcium absorption from food in the intestine, via its effects on vitamin D metabolism.
• PTH has no effect on carbohydrate metabolism.