UPSC CSE Prelims
Question 89
Consider the following statements:
- Coal ash contains arsenic, lead and mercury.
- Coal-fired power plants release sulphur dioxide and oxides of nitrogen into the environment.
- High ash content is observed in Indian coal.
Which of the statements given above is/are correct?
View correct answer and explanation
Correct answer: D
Correct Option: D (1, 2 and 3)
Explanation: Coal combustion produces ash containing toxic trace metals, emits sulphur dioxide and nitrogen oxides, and Indian coal often has relatively high ash content.
Statement / Pair / Item-wise Analysis:
1. Correct - Fly and bottom ash can contain arsenic, lead and mercury at trace concentrations.
2. Correct - Coal power plants emit SO2 and NOx unless suitably controlled.
3. Correct - Many Indian coal grades contain comparatively high mineral ash fractions.
Option-wise Analysis:
A. Incorrect-omits correct item 2 (Coal power plants emit SO2 and NOx unless suitably controlled); omits correct item 3 (Many Indian coal grades contain comparatively high mineral ash fractions).
B. Incorrect-omits correct item 1 (Fly and bottom ash can contain arsenic, lead and mercury at trace concentrations).
C. Incorrect-omits correct item 1 (Fly and bottom ash can contain arsenic, lead and mercury at trace concentrations); omits correct item 2 (Coal power plants emit SO2 and NOx unless suitably controlled).
D. Correct-includes all and only valid statements/items 1, 2, 3.