Debaki Prashad,58yrs,who had backache and recurrent chest infections for 5 months, develops sudden weakness of the legs and urinary retention. Her investigations show a hemoglobin of 7.8 gm/dl,serum calcium 12.6 mg/dl, phosphate-2.5 mg/dl, alkaline phosphatase-100u/l,serum albumin-3 gm/dl,globulin-7.1 gm/dl and urea-171 mg/d. What is the most likely diagnosis?

• A. Disseminated tuberculosis
• B. Lung cancer
• C. Osteoporosis
• D. Multiple myeloma