Which of the following is used to differentiate between hypercalcemia of malignancy from primary hyperparathyroidism?

Answer- A. Hydrocoisone suppression testlf doubt exists, hyilrocokone suppression test is of value.If the test is performed as originally described, (120 mg hydrocoisone per day for 10 days, correcting the serum calcium for haemodilution), it provides an excellent discrimination, since significant suppression ofserum calcium does not occur in primary hyperparathyroidism, where as malignant hypercalcemia is usually completely alleted.