The correct answer is B. A teacher works one-on-one with a student and then begins to withdraw help as the student becomes more skilled.
Explanation:
For Lev Vygotsky who was an important Soviet psychologist, the term "scaffolding" refers an instructional technique that purposes students need guidance from a teacher or a more advanced student to achieve step by step learning goals. This is linked to the concept of "zone of proximal development" in which students are unable to achieve learning goals by themselves but able to do it with the support of others. This also implies students are guided at the beginning but then as they advance they are independent. Considering this, the option that illustrates this concept is " teacher works one-on-one with a student and then begins to withdraw help as the student becomes more skilled".