Consider- the following statements: 1) Coal ash contains arsenic, lead and mercury. 2) Coal-fired power plants release sulphur dioxide and oxides of nitrogen into the environment 3) High ash content is observed in Indian coal. Which of the statements given above is/ are correct?

All three statements are correct, so the answer is D. Statement 1: coal ash, both fly ash and bottom ash, carries trace toxic elements such as arsenic, lead, mercury, cadmium and chromium. This is why ash ponds near thermal plants are a groundwater concern.

Statement 2: sulphur in coal oxidises to sulphur dioxide during combustion, and high flame temperatures fix atmospheric nitrogen into oxides of nitrogen. Both are precursors of acid rain and secondary particulate matter, and their limits are set under the Environment (Protection) Act through MoEFCC emission norms.

Statement 3: Indian coal is typically high in ash, often 30 to 45 percent, and comparatively low in calorific value. This is the reason for the import-blending debate and for the focus on fly ash utilisation.

Core concept: coal quality and combustion pollution, which links to energy security and environmental governance in GS-3. Mains angle: the fly ash utilisation rules that require thermal plants to supply ash to cement and brick makers.

Trap: aspirants pick B by doubting statement 1 because the heavy metal claim sounds too technical, or by dismissing statement 3 as a minor issue. All three are standard facts.