Answer: The answer is C.
Explanation: If you choose A, the container can still break even if you have a covering on it. It can also release harmful insecticide in your home and may cause lung damage if inhaled.
If you choose B, insecticides aren't that harmful to humans if the container is closed. However, if it is open, the container may be dangerous to humans.
If you choose D, even if it is out of reach of children, it is still harmful even if it is open.
So, therefore, the most logical answer is C: the container is unlabeled and may be mistaken for food.