The survivors of the crashed plane had no food or water and were ________ the extreme cold weather.[ ]

A. in the possession of  

B. in the charge of

C. at the mercy of  

D. at the risk of

集体草原和集体长期固定使用的全民草原，由下列哪一级机关登记造册，核发证书，确认所有权或使用权( )

A．乡级人民政府

B．乡级以上人民政府

C．县级人民政府

D．县级以上人民政府