What is the main drawback of a standard open differential when one of the drive wheels loses traction on a slippery surface (like mud or ice)?

1. The wheel with traction receives all the torque, stalling the vehicle.
2. The wheel with no traction spins rapidly while the wheel with traction remains stationary, preventing the vehicle from moving.
3. The differential case locks up and stops the engine.
4. Both wheels spin at the exact same speed, causing the vehicle to slide sideways.