<prompt> which of the following is a Bone resorption marker is ?Serum propeptide of type I procollagenOsteocalcinUrine total free deoxypyridinolineFree glutamic acid cross linkage  <response>: Deoxypyridinoline DPD in urine, which reflects systemic bone resorption, is considered most useful for assessing the effects of osteoporosis treatment. 