At an island in the Indian ocean ,at a distance of 300 meters from the shore ,the depth of water is 500 meters .The surface temperature of water at this distance is 20 oC . Because of this sharp bathymetry curve (depth vs distance ) the difference in temperature of water between the surface and the ocean floor is 15 o C , at such a short distance of 300 meters . A floating power plant that utilizes this temperature differences could be built . What could be the maximum efficiency of this plant ( choose from A = 25% B =15 % C =10 % D = 5 %)