An example of is one in which a group of individuals who have a condition, such as heart disease, are compared with a similar group of people who do not have the same condition. A. a case control study

B. a human study

C. an intervention study

D. a cell culture stydy

Because without physical activity, the body has extra "energy" if you will, and so when it is time for bed you are not tired, so you end up staying up all night. also there is probably an effect on your internal clock, which messes with your melatonin production which goes hand in hand with your sleep cycle

Broken bone result of heredity