Incinerators are used for which of the following?

1. A

   Burning wastes

   (a) Official key: Incinerators are used for burning wastes. High-temperature combustion reduces volume of municipal or hazardous waste. Among the four uses, burning is the official function.

2. B

   Putting wastes into them

   Putting wastes into a box or pit is dumping or landfilling, not incineration. Storage is not the keyed use.

3. C

   For cutting green trees

   Cutting green trees is forestry or illegal felling, unrelated to an incinerator. This option is a nonsense distractor.

4. D

   For making fertilizers

   Making fertilizers is composting or chemical industry, not incineration. Burning waste does not define fertilizer manufacture.

Summary. Official key is (a). An incinerator is a furnace for burning waste. Dumping, tree-cutting and fertilizer-making are different operations. Keep burning wastes. The official letter is (a).