Microorganism !! Please brainly ?
Allergies, so they don't ingest something they are allergic to.
Technically any of these. Are there any other details or specifics. I'd assume participating in sports because a diet only helps stress levels in the long term, watching television can relax a person but the other factors such as lack of social activity can contribute to a person's overall mental state and therefore increase stress levels, and studying can actually be relieving for some people depending on the mental state and needs of them but can obviously be a stresser. The only downfall to participating in sports is getting to excited or emotional during a game for example. But overall, C is the best choice.
It is a good idea because it helps to detect if there is too much carbon monoxide in the house. If there is too much, it can be poisonous and the detector will let you know. this answer would be TO AVOID POISONING BY A BUILDUP OF CO GAS.
btw, is this platoweb? just curious.