when the catalyst of a catalytic converter is contaminated with lead and silicone, then the converter must…

when the catalyst of a catalytic converter is contaminated with lead and silicone, then the converter must be typically \n \n a. restored by correcting any conditions that caused the contamination \n b. replaced \n c. serviced by driving the vehicle for an extended time at freeway speeds \n d. cleaned
Answer
Brief Explanations:
Lead and silicone are poisons for catalytic converter catalysts. Once contaminated, the catalyst's structure and function are severely damaged. Correcting contamination - causing conditions (option a) won't fix the already - poisoned catalyst. Driving at freeway speeds (option c) is a way to deal with some minor performance - related issues (like carbon buildup in some cases), but not for lead and silicone poisoning. Cleaning (option d) is ineffective against the strong bonding and structural damage caused by lead and silicone. The only practical solution is to replace the converter.
Answer:
B. Replaced