How far must you stop from a school bus with flashing lights?

Answer: C — 20 feet

When approaching a school bus that has its flashing lights activated, you are required to stop at least 20 feet away from the bus. This rule is in place to ensure the safety of children who may be getting on or off the bus. The substantial distance allows adequate space for children to enter or exit safely without the risk of being struck by a vehicle. Additionally, this law emphasizes the importance of slow and cautious driving in areas where children are likely to be present, reinforcing the need for heightened awareness near school zones and bus stops. The other options do not provide sufficient distance to guarantee the safety of children, making 20 feet the correct and legally mandated stopping distance.