A space-based radio-navigation system consisting of satellites and a network of ground stations used for monitoring and control is called:

A space-based radio-navigation system consisting of satellites and a network of ground stations used for monitoring and control is called:

A space-based radio-navigation system consisting of satellites and a network of ground stations used for monitoring and control is called: 










A. UTM.
B. GPS.
C. SMDRT.
D. UMS.










Answer: B