If a driver accidentally misses their intended exit ramp while driving on an expressway, what is the ONLY legal and safe course of action?

1. Stop immediately, engage reverse gear, and back up along the shoulder to the missed exit
2. Make a quick U-turn across the central median service opening
3. Continue driving forward to the next available exit interchange, exit the expressway, and reroute (继续向前行驶至下一出口驶离)
4. Cut directly across two traffic lanes to dive into the exit ramp