Every year the farmer was taking care of his ice field, keep it clean and clear of all the unnecessary shrubs and then reuse the debris to fertile the soil again and then grow rice again. But since he fell sick, there is no one to take care of his rice field which will leads to the growth of unnecessary plants and weeds in it.
There will grow wild plants and shrubs which will contaminate the rice field.
A habitat defines the interaction of organisms with the other factors, which can be living or non-living, while niche describes how that specific organism is linked with its physical and biological environment. Habitat is the part of the ecosystem, while niche plays an important role in the formation of an ecosystem.
If i am not mistaken , the answer is C