(B) is incorrect because we lack support for the idea that toddlers bite to gain attention. The example given in the passage indicates that a child may bite because they want a toy. It says nothing about the child doing so because they want attention. This difference may be tricky to see at first, but wanting the toy is distinct from wanting attention from adults. Based only on this information and not our outside knowledge, we cannot make the unwarranted assumption that toddlers sometimes also bite for attention from adults.
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