2024 OK CDL Practice Test: Double and Triples - Test Based on 2024 OK CDL Handbook 26. Who is responsible for the safe operation of a vehicle? A The driver B The owner C The mechanic Next More 26/30 Progress 0 Errors Restart Next Next Double and Triples - Test Back to Test List Passenger - Test 2 Double and Triples - Test 2 Challenge Library 12 More OK CDL Practice Tests 25 Double and Triples - Test 2 26 Double and Triples - Test 3 27 Double and Triples - Test 4 28 Double and Triples - Test 5 29 Tank - Test 30 Tank - Test 2 31 Tank - Test 3 32 Tank - Test 4 33 Tank - Test 5 34 Air Brakes - Test