A) Skills children can do alone
B) Skills children can do with guidance
C) Skills beyond child's capacity even with help
D) Reflexive behaviours
Answer: B
Explanation: ZPD is the gap between what a learner can already do independently and what they can achieve with the help of a more knowledgeable other. It is the most effective zone for instruction because learning happens best when tasks are slightly beyond the learner's current independent ability but achievable with guidance.