Two children score alike alone; with hints, one does far more. Vygotsky says:

1. Both children have the same actual level (what they do alone). 2. With help, one child reaches a much higher level than the other. 3. The ZPD is the distance between the solo level and the assisted level. 4. Vygotsky asked whether two children with equal test scores are at the same level of development. 5. His answer was no: the child who gains more with help has a wider ZPD. 6. So their zones of proximal development differ, even though their test scores match. **Why the other options fail:** - Their levels are equal is what a solo test would wrongly conclude. - The other two options reject assisted performance, which is the heart of his view. _Source: Wikipedia, "Zone of proximal development", section "Origins" (revision 1365068534)_