What is the primary purpose of Mr. Vaughn's questioning strategy?

The primary purpose of Mr. Vaughn's questioning strategy focuses on extending a specific student's knowledge—in this case, Sam. This approach is essential in a classroom setting because it not only engages the student directly in their learning process but also challenges them to think critically and explore concepts in depth.

By utilizing questions that push Sam's understanding further, Mr. Vaughn fosters an environment where inquiry and exploration are encouraged. This strategy often leads to a deeper comprehension of the subject matter, as students are prompted to articulate their thoughts, make connections, and reflect on their learning. Expanding a student's knowledge base in this manner is fundamental to effective teaching, as it caters to individual learning needs and promotes academic growth.

In the context of the other options, while encouraging peer interaction, assessing student knowledge, and providing immediate feedback are valuable practices in education, the specific intention here is to amplify Sam’s learning experience specifically through targeted questioning. This highlights the adaptiveness of Mr. Vaughn’s teaching style to prioritize students’ developmental needs.