The correct answer is C) concentrated high and the double bottoms are empty. A vessel would be referred to as "tender" when the weight of the cargo is concentrated high and the double bottoms are empty. This is because when the cargo is concentrated high, it raises the center of gravity of the vessel, making it more susceptible to rolling and becoming unstable, or "tender." With the double bottoms empty, there is less weight low in the vessel to counteract this high center of gravity. The other options are incorrect because they do not describe a situation where the vessel would be considered "tender." A vessel with cargo weight concentrated low and full double bottoms (A) or evenly distributed vertically with full double bottoms (B) would be more stable and less tender. A vessel with cargo weight concentrated low and empty double bottoms (D) would also be less prone to tenderness.