If there is no oxygen , the cells go through anaerobic respiration which leads tot he build of lactic acid in the muscles. This is why we get sore and feel the burn during a workout.
AN EPIDEMIC is a disease that affects a large number of people within a community, population, or region. example coronavirus .
If NOCTURNAL ACTIVITY is one of the choices, that's your answer.
Answer: B
Explanation: Hope this helps :)