Technician A says that the purpose of the oxygen sensor located after the catalytic converter is to measure the amount of unburned hydrocarbons that were not oxidized by the converter. Technician B...

Technician A says that the purpose of the oxygen sensor located after the catalytic converter is to measure the amount of unburned hydrocarbons that were not oxidized by the converter. Technician B says that the purpose of the oxygen sensor located after the catalytic converter is to monitor the catalytic converter’s effectiveness. Who is correct?

A. Technician A only

B. Technician B only

C. Both technicians

D. Neither technician