The sentence can be complete with option D " the Ross and Ronne ice shelves are major land forms in Antarctica". The Ross ice shelf might be considered the largest land form in Antarctica because it seems to be around the size of France. As regards, the Ronne ice shelf, it could be said that it borders the Weddell Sea.
In the case of high evaporation rates, the local government can manage water supply by scheduling a rotating water outage. The outage can be set to the hours when the evaporation rate is the highest. This will allow the citizens to save up water and use it wisely.
I don't have enough information to give a correct answer