The responses suggest multiple similarities between the passages. To determine which one builds on the same idea, consider what overarching theme connects the passages.
If both passages emphasize the dangers associated with cell phone usage, then:
A ("Both passages mention the potential harm of using cell phones") and B ("Both passages show the negative health effects of cell phones") are closely related. They both address the consequences of using cell phones, though B is more specific about "negative health effects."
Responses C and D focus on different themes related to social interactions and parental involvement, which may not align with the central idea if the main focus is on cell phones.
Without more context about the passages, A or B would likely be the similarities that build on the same idea, with B providing a more detailed angle on health specifically. Still, A sets a broader context stating potential harm, which may encompass health as well as other problems.
In conclusion, responses A and B are closely linked, but B might be seen as a more refined focus if the passages target health effects directly.