Drought and floods both are the natural disasters in which there is the extreme scarcity of water due to the absence of rainfall and floods due to heavy rainfall. Drought results in infertile agricultural lands due to nonavailability of water for crop production. Hence there is no food and water for the organisms in that area that results in either migration of organisms or their death. Flood makes soli saline and erodes the fertile soil that affects the crop production even it damages the flora, fauna and other infrastructure. Thus, the correct answer is option D.