Final answer:
Katherine suggests that the newsies adapt to the changing times by continuing to sell newspapers.
Step-by-step explanation:
Katherine suggests that the newsies adapt to the changing times by maintaining their current strategies. In the context of the question, this means that Katherine suggests the newsies continue selling newspapers.
This can be seen in the text where it mentions that newspapers have turned to social media to stay visible and profitable, indicating that selling newspapers is still a viable option for newsies. It is important to note that Katherine does not suggest starting a revolution, organizing an exclusive interview, or printing sensational news to sell papers.