D). She had a history of criminal activity and mental illness.
Explanation:
The title 'Good help is hard to find' clearly portrays the author's intent to warn the audience through this incident. The passage displays the struggle of a father who is seeking a babysitter for his 'twin toddlers'. He got an ad published in the newspaper to make his task easier. He interviewed people and finally reached to selecting two women out of whom he thought that one would be the best.
But then comes a major shock to him when he reads in the newspaper about the pervasive criminal history and mental illness of one of the women. Thus, he could not hire her which proves fruitful as he read a few days later about the attack on a little child made by that woman. Therefore, option D clearly states the reason for not hiring one of the women.
