When driving a passenger bus on an unpaved muddy rural road after heavy rain, what is the best technique to prevent getting stuck or sliding off the road?

1. Follow in existing firm tire ruts, maintain a steady low gear, keep the steering wheel steady, and avoid abrupt braking, gear changing, or sharp steering
2. Drive on the soft road shoulder where water accumulates to test mud depth
3. Accelerate aggressively in top gear to spin the drive wheels out of the mud
4. Weave back and forth across the road to generate friction heat on the tires