Which glands produce a hormone that maintains the balance of calcium and phosphorus in the blood?

Parathyroid glands.

Explanation:

The parathyroid glands are small endocrine glands that are located behind the thyroid gland in the neck. Its primary function is to secrete a parathyroid hormone (PTH), responsible for controlling and maintaining the balance of calcium and phosphorus in the blood within certain limits. This helps to achieve proper functioning of the muscles and nerves, and also helps maintain strong bones.

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?

the answer would be   10%