As the name implies, anaerobic means there is no presence of oxygen. So if it will take place, it will only take place in little or no oxygen which is in the last sentence in the following choices. First and second choice are wrong for there is a need of oxygen required when there is no oxygen is needed and the presence of nitrogen in water.
Answer:
a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. Electrons should move around the nucleus but only in prescribed orbits.
Explanation: