Which statement about skids and jackknife is correct?

1. This answer would create an unsafe coupling, braking, turning, or inspection habit.
2. This choice is not supported by the Texas CDL handbook or FMCSA combination-vehicle standards.
3. If trailer wheels lock and skid, release the brakes so the wheels can roll.
4. This statement confuses the tested combination-vehicle rule with an unrelated CDL topic.