Which of the following statements is/are correct? 1. Thermal power stations in Delhi were required to summarily shut down. 2. CNG supplies had to be assured once diesel vehicles were prohibited from plying. 3. The Supreme Court banned the use of coal across the National Capital Region. Select the answer using the code given below.

Statement 1 is incorrect: the passage says thermal power plants were to 'clean up OR shut down', not summarily shut down. Statement 2 is correct: the passage explicitly says when diesel buses were stopped, CNG supply had to be assured. Statement 3 is incorrect: the passage says the Delhi Government (not the Supreme Court) banned coal, and it was later extended to the entire NCR — the ban was not by the Supreme Court. Hence only statement 2 is correct.