Final answer:
Lev Vygotsky's view of mental and behavioral development is best represented by scenario C, where a teacher assigns challenging tasks to students but then helps them by showing.
Step-by-step explanation:
Lev Vygotsky's view of mental and behavioral development is best represented by scenario C, where a teacher assigns challenging tasks to students but then helps them by showing. Vygotsky believed that learning occurs through social interaction and that more knowledgeable individuals can assist and guide learners in their development. By assigning challenging tasks and providing support, the teacher is promoting the zone of proximal development, which is the range of tasks that a learner can accomplish with guidance.