A 53-Year-Old Man with Multiple Myeloma Is Hospitalized After 2 $\left[\mathrm{Ca}^{2+}\right]$

Multiple Choice

A 53-year-old man with multiple myeloma is hospitalized after 2 days of polyuria, polydipsia, and increasing confusion. Laboratory tests show an elevated serum $\left[\mathrm{Ca}^{2+}\right]$ of $15 \mathrm{mg} / \mathrm{dL}$ , and treatment is initiated to decrease it. The patient's serum osmolarity is $310 \mathrm{mOsm} / \mathrm{L}$ .
-The treatment drug is administered in error and produces a further increase in the patient's serum $\left[\mathrm{Ca}^{2+}\right]$ . That drug is

A) a thiazide diuretic
B) a loop diuretic
C) calcitonin
D) mithramycin
E) etidronate disodium