In Vygotsky's theory, the zone of proximal development refers to

	a.	the amount of variability in behavior tolerated.
	b.	an area in which tasks are too difficult for a child to solve alone but in which they can be solved with the support of others.
	c.	the projection of the physical growth curve from infancy to adolescence.
	d.	the area in which an infant feels secure without direct contact with the primary caretaker.