What is the primary danger when riding a motorcycle through standing puddles of water on the roadway?

1. The puddle may conceal deep potholes, rocks, or mud, and can cause instant hydroplaning (aquaplaning)
2. Water splashed onto the engine will crack the cylinder head through thermal shock
3. Puddles are safe to ride through at speed because water offers no resistance
4. The only risk is that the rider's boots and clothing become wet