Which of the following statements are true of parathyroid hormone (PTH) and calcitonin? (Read carefully and select all of the correct statements.)

A)Both hormones are secreted by the parathyroid glands.
B)PTH increases the storage of calcium in bones.
C)Calcitonin increases the reabsorption of calcium by the kidneys.
D)PTH stimulates the activation of vitamin C by the kidneys.
E)PTH increases the absorption of calcium from food in the small intestine
F)Calcitonin is secreted when the blood calcium level decreases.