सूची I के साथ सूची II का मिलान कीजिए: सूची I (जल प्रदूषक प्रकार) (A) विषाक्त प्रदूषक (B) गैर-विषाक्त प्रदूषक (C) स्थूल प्रदूषक (Macroscopic) (D) रोगजनक प्रदूषक (Pathogenic) सूची II (उदाहरण) (I) क्लोरीन (II) प्रोटोजोआ (III) बेंजीन (IV) खाद्य डिब्बे (Food cans) नीचे दिए गए विकल्पों में से सही उत्तर चुनिए:

The approach of combining multiple methods, data sources, or investigators in the study of the same sociological or scientific research phenomenon is known as:

Given below are two statements: Statement (I): The near-complete absence of fluoride in drinking water causes tooth decay. Statement (II): Excessive concentrations of fluoride in drinking water cause mottling of teeth, also known as dental fluorosis. In the light of the above statements, choose the most appropriate answer from the options given below: