What component's failure is likely to trigger rejection of an exhaust system inspection?

The rejection of an exhaust system inspection is most likely triggered by the failure of the catalytic converter. This component plays a crucial role in reducing harmful emissions produced by the vehicle's engine. It converts exhaust gases into less harmful substances before they exit the exhaust system. If the catalytic converter is malfunctioning or has been removed, it not only increases emissions but may also lead to noise and performance issues.

Inspection standards are strict regarding the catalytic converter because it is essential for compliance with environmental regulations. Vehicles must meet specific emissions criteria, and a defective catalytic converter can result in the vehicle failing an emissions test, thereby leading to a rejection of the exhaust system inspection.

The other components mentioned, while important for the overall function of the exhaust system, do not typically carry the same weight when it comes to emissions standards. Exhaust system hoses and muffler clamps are less likely to critically affect emissions and therefore might not lead to an automatic rejection. Tail lights, on the other hand, are unrelated to the exhaust system's function.