निम्नलिखित में से कौन सा उपकरण मुख्य रूप से औद्योगिक उत्सर्जन से कणीय पदार्थ (particulate matter) को नियंत्रित या एकत्रित करने के लिए उपयोग नहीं किया जाता है?

Consider the following statements regarding air pollution mitigation strategies: Statement I: Reducing emissions at the source is considered the most effective scientific approach to controlling air pollution. Statement II: Measures such as smog towers and artificial cloud seeding are also employed as supplementary interventions in urban air pollution management. Which one of the following is correct in respect of the above statements?

Which of the following devices fitted in vehicular exhaust systems helps control air pollution?