Practice question Why support air lines? To shorten trailersTo prevent dragging, snagging, chafing, and disconnectionTo replace chainsTo disable ABS lights Answer: B — To prevent dragging, snagging, chafing, and disconnection The correct answer is shown above. Try the full quiz for additional practice. Practice more: Washington CDL Doubles and Triples Endorsement Test Practice Questions - Washington CDL Doubles and Triples Endorsement Test Exam →