Which of the following is an example of a serious traffic violation?

Serious traffic violations include excessive speeding (15 mph or more above the posted limit); reckless driving; improper or erratic lane changes; following a vehicle too closely; traffic offenses committed in a CMV in connection with fatal traffic accidents; driving a CMV without obtaining a CDL or having a CDL in the your possession; and driving a CMV without the proper CDL class and/or endorsements.