What is classified as a school bus?

A school bus is defined specifically as a motor vehicle that is designed and used primarily to transport students to and from school for educational purposes. This classification includes vehicles that operate on established routes for transporting children to and from their educational institutions, adhering to safety regulations specific to school buses.

The focus on transportation for educational purposes in the correct answer aligns with legal definitions and regulations governing school transportation, which prioritize the safety and welfare of students. Other vehicle types mentioned, such as those for recreational purposes or private school activities, do not fit this description, as they do not primarily serve the educational transportation function that is characteristic of school buses. Additionally, a van used for after-school programs may serve a supplementary role but is not classified as a school bus under the same legal and regulatory framework. Thus, option B accurately captures the essence of what constitutes a school bus.