Calcium blood levels are very tightly regulated with the aid of parathyroid hormone and vitamin D. The statements below represent actions that take place during times of low blood calcium, times of high blood calcium, or neither. Match below mention statements with them.

a. Increased vitamin D activation leads to decreased calcium absorption from the intestines.
b. Increased production Of PTH stimulates activation of vitamin D.
c. Parathyroid glands increase secretion of PTH.
d. Less calcium is reabsorbed by the kidneys.
e. Parathyroid glands decrease secretion of PTH.
f. Osteoclasts are inhibited. leading to decreased breakdown of bone.
g. PTH and vitamin D Stimulate increased breakdown of bore.