Which of the following is true of insulin?

a. secreted by the posterior pituitary gland
b. deficiency causes diabetes insipidus
c. secreted in response to decreased blood glucose
d. regulate blood glucose

d. helps regulate blood glucose

Explanation:

The insulin hormone is secreted by beta cells of the endocrine portion of the pancreas. Insulin is released in response to raised blood glucose levels. The function of this hormone is to make the body cells to take up the glucose from the blood. It specifically targets the liver and muscle cells and makes them absorb glucose from the blood. The absorbed glucose is stored in the form of glycogen in these cells and the blood glucose levels are restored to the normal range.

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.