<prompt> Which of the following is seen in osteoporosis -Low Ca, high PO4, high alkaline phosphataseLow Ca, low PO4, low alkaline phosphataseNormal Ca, normal PO4, normal alkaline phosphataseLow Ca, low PO4, normal alkaline phosphatase  <response>: Serum calcium, phosphate and alkaline phosphatase are normal in osteoporosis. 