Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Example: In 1582 the united provinces invited francis, duke of anjou to lead them; but after a failed attempt to take antwerp in 1583, the duke left the netherlands again. after the assassination of william of orange (10 july 1584), both henry iii of france and elizabeth i of england declined the offer of sovereignty. however, the latter agreed to turn the united provinces into a protectorate of england (treaty of nonsuch, 1585), and sent the earl of leicester as governor-general. this was unsuccessful and in 1588 the provinces became a confederacy. the union of utrecht is regarded as the foundation of the republic of the seven united provinces, which was not recognized by the spanish empire until the peace of westphalia in 1648.
Example solution: In what year did francis, duke of anjou leave the netherlands?
Example explanation: The generated question is perfect. Because the question is based on second sentence of the input passage and its answer is 1583.

Problem: Bone pain is a common symptom in bone metastases. The therapies that are currently available include nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, steroids and gabapentin which have been demonstrated to improve neuropathic pain. In addition, preclinical studies indicate that agents such as transient receptor potential vanilloid 1 antagonists and cannabinoid 2 receptor agonist could be considered as adjuncts in ameliorating opioid side effects. New drugs are in the clinical phase of development, among which the most promising molecules seem to be anti-nerve growth factor (NGF) antibodies. Anti-NGF antibody therapy may be particularly effective in blocking bone cancer pain because NGF appears to be integrally involved in the upregulation, sensitization and disinhibition of multiple neurotransmitters, ion channels and receptors in the primary afferent nerve. The best way to treat bone metastases pain is to improve the control of skeletal disease burden. Recently, denosumab, a noncytotoxic IgG2 monoclonal antibody with high affinity for human RANKL, has been demonstrated to significantly prevent clinically relevant increase in pain compared with zoledronic acid across the tumor types. Based on these data, it has been suggested that denosumab has the potential to become a new standard of treatment in bone metastases management.
Solution: To the ligand of which receptors does Denosumab (Prolia) bind?