In an ecosystem abiotic components like nutrients, water, sunlight, climate are essential for a producer to produce food. These producers are organism having chlorophyll in them i.e plants and trees. Once the food is produced , a consumer is required to consume the food thus herbivores are necessary as they only feed on plants and trees. Now if carnivores are removed from the ecosystem, the next stage would be the decomposition of dead animals and plants by the decomposes to bring back the entrapped nutrients into the soil again.
Thus, carnivores are not that important for survival of an ecosystem.
An ecosystem is a physical environment involving living (plant, animal and human) and non-living components (sun, water and soil). Living components are dependent upon non-living components for their survival. But they can sustain their lives even in the absence of non-living components. The ecosystem probably survive without carnivores and climate. Carnivores are organisms which feed upon other organisms. Carnivores are grouped in highest trophic level in a food chain. If carnivores are removed from the ecosystem a ecosystem can sustain the life of lower trophic levels in a food chain. Therefore, ecosystem can survive without carnivores. A change in climate can affect life forms living in an ecosystem. But if life forms can undergo adaptations to tolerate the change in climate then an ecosystem would probably survive without appropriate climate.
The answer is A. melting. The change from gas to liquid to solid will release energy and the change from solid to liquid to gas will absorb energy. So the other three are releasing energy.
