Please I have so much more to do.

The correct answer is D. Skeletal system.

Explanation

The parathyroid glands are glands of the human endocrine system that are located behind the thyroid glands in the neck. The main function of the parathyroid glands is to control the amount of calcium in the body (mainly bones and blood). According to the above, the parathyroid glands produce essential hormones for the proper function of the bone system because it controls the calcium that is used to strengthen the bones. These at the same time serve as the storage system to ensure that the body always has a vast source of calcium. So the correct answer is the D. Skeletal system.

hi, natural selection of the peppered moth during the industrial revolution in 19th-century england is an example of an outlier in the study of evolution. during this time, pollution from factories filled the forests, coating trees in a layer of soot—turning white trees black

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gokuson

i dont know this but ask your teacher for !