Incinerators are used for which of the following?

The correct answer is A. An incinerator is a furnace designed to burn solid, liquid or gaseous waste at high temperature, reducing its volume and often its hazard. Hospital waste, municipal solid waste and sludge are common inputs, and the ash that remains is much smaller in bulk than the original waste.

Here is why the other options fail:

• B: Loading waste into the furnace is only a step in the process. It describes how the device is fed, not what it is used for.
• C: Incinerators do not cut trees. Timber is felled and sawn by axes, saws and sawmills, and green wood is not a waste-burning input.
• D: Fertilizers come from composting, vermicomposting or bio-methanation, which use microbial decomposition. Burning produces ash and heat, not fertilizer.

The core concept is thermal waste treatment. For Mains, link it to the Bio-Medical Waste Management Rules, 2016, which regulate incineration of hospital waste, and to the debate on waste-to-energy plants, where dioxin and fly-ash emissions are the main concerns.

Trap: Aspirants pick B because it describes the operation of loading the furnace. Always ask what the machine is for, not what is done before using it.