Thursday morning when I went to put my walking shoes on by the front door , I noticed several ants crawling around on the floor . Where did those come from ? I never had ants in here before . Since then I have been finding ants on the living room floor , and now in the kitchen .

Generate a question about the above context.
What 's a possible reason there were ants crawling around on the floor ?
Select from the following. 1. None of the above choices .. 2. Because there was some food spilled or left out .. 3. Because the writer never had ants in there before .. 4. Because it was Thursday morning ..