After successfully coupling, the driver raises the landing gear and performs a final visual inspection. What specific detail must the driver confirm by looking at the fifth wheel connection?

1. The release handle is in the fully open position.
2. There is a slight gap between the top of the fifth wheel and the trailer apron for lubrication.
3. The kingpin is visible above the locking jaws.
4. There is no space between the tractor's fifth wheel and the trailer apron, and the locking jaws are closed around the kingpin's shank.