Technician a Says That the EPA Highway Diesel Rule Permits

Technician A says that the EPA Highway Diesel Rule permits NG-fueled engines to output higher NOx emissions. Technician B says that the EPA Highway Diesel Rule focuses on the entire rig and therefore includes factors that influence fuel economy that are not engine-related. Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B