What is the minimum distance passengers leaving a school bus should cross in front of the bus?

Answer: C — 3 metres

Passengers leaving a school bus should cross at least 3 metres in front of the bus. This is because buses have a large blind spot directly in front of them, and the driver may not be able to see someone who is too close. Options A and B are too close and could put the passengers at risk. Option D is too far and could also create an unsafe situation. Therefore, the minimum distance of 3 metres is the safest and most appropriate option.