Old or late adulthood is the stage of growth in which diseases are easily and always present and sometimes due to weak immune system and other cause are chromatic diseases. Skin continues to lose elasticity, reflexes starts to slow and same with their reaction time. mobility and muscles strength begins to decrease, hearing and vision begins to dull. Mostly people with this age may have a lower function in their brain leading to intellectual diseases such as Alzheimer's disease.
Answer: I would say option D because it seems the most logical and you shouldn't be avoiding your schoolwork, getting less sleep, or eating unhealthy food because those would make you feel bad and have it worse than it is already and exercising can make feel a lot better and also look better too.
Explanation: