The discussing sharing of a communication satellite by many geographically dispersed Earth station, DAMA means

ANS:A - Demand-Assigned Multiple Access

Demand Assigned Multiple Access (DAMA) is a technology used to assign a channel to clients that don't need to use it constantly. DAMA systems assign communication channels based on requests issued from user terminal to a network control system. When the circuit is no longer in use, the channels are then returned to the central pool for reassignment to other users.