If you note a major defect on your bus, you must...?

Answer: B — not drive it

If you note a major defect on your bus, you should not drive it. Continuing to drive could risk further damage to the bus, putting yourself and others in danger. Reporting the defect is the responsible thing to do, but driving with it could result in serious consequences. Choosing to only drive during daylight would not resolve or eliminate the danger of driving with a major defect. The only safe and appropriate option is to not drive the bus until the defect has been addressed.