The answer to this is C. The waste bin should be removed when the bin bag is full. Others may say that it has to be done every day. This is ideal if you use your kitchen all the time and you have a lot of waste products. This can be a waste if it usually takes days before the waste bin is full. Do remember that it will also depend on the type of wastes that you place.
Do you normally throw items that can decompose easily? If yes, then you need to throw away the wastes as often as you can. If you are only placing dry items in the waste bin, there is a bigger chance that your wastes can stay longer inside your kitchen. Remember that this is still something that would depend on you.
Kitchens are used to cook food. It is probably the most important room in the house that needs to be kept the cleanest. Since people prepare food, they would not want to lay the food on the counter when it is completely dirty and filled with germs. That might make the members of the family sick due to the ingestion of germs from the foods.
So, the members of the family should remove the waste from the kitchen as soon as possible. A lid on the garbage can is needed in order for the germs not to spread. If the garbage spilled onto the floor or another surface, it could spread germs or uncooked meat could touch other foods. This would contaminate the food.