<prompt> In osteomalacia which of the following biochemical feature is true?Elevated serum calcium levelElevated serum phosphate levelElevated serum alkaline phosphataseElevated 25-hydroxyvitamin D3  <response>: In osteomalacia, serum ALP alkaline phosphatase levels are raised, 25OHD levels are low or undetectable, PTH is elevated, serum calcium and phosphate levels may also be low but normal values do not exclude the diagnosis. Reference : page 1127 Davidsons Principles and practice of Medicine 22nd edition 