Answer:
The bacteria found on roots, mainly on legumes, are related to the nitrogen cycle because nitrogen found in the environment is not usable by many species but because the bacteria can "fix" the nitrogen, it is usable by the plant which in turn it returned into the environment.
Explanation:
In my opinion it is tears.
This can affect the organisms living there because now, their environment is probably different than what they have been living in for a long time, so now they have to adapt to this new environment, and if they don't, the organisms will probably end up dying.
Death rate is lower than birth rate, and immigration equals emigration would lead to an increasing population.
Option D is the correct answer