The hand-off problem ensuring that the driver is paying

Question

Which of the following difficulties in creating a Level 3 Self-Driving Car:

1. The hand-off problem (ensuring that the driver is paying attention when the autonomy system needs to revert control back to the driver)
2. Operations in adverse weather (rain, snow, fog, direct sunlight)
3. Ensuring that the vehicles a priori map is accurate (i.e., no road construction or major changes appearance of the road surface)
4. All of the above