UPSC Prelims 2014— Question 58

Correct answer: Option D. Coalbed methane is predominantly methane associated with coal seams. Shale gas is natural gas trapped in fine-grained shale formations and is not merely a propane-butane mixture. India has identified shale-gas potential as well as coalbed methane resources, so the statement that no shale gas sources have been found is also incorrect. Hence neither statement is correct. Option A: Incorrect. This option does not match the verified answer because its proposition, location, institution, sequence, or combination conflicts with the relevant fact tested in the question. The option reads: “1 only” Option B: Incorrect. This option does not match the verified answer because its proposition, location, institution, sequence, or combination conflicts with the relevant fact tested in the question. The option reads: “2 only” Option C: Incorrect. This option does not match the verified answer because its proposition, location, institution, sequence, or combination conflicts with the relevant fact tested in the question. The option reads: “Both 1 and 2” Option D: Correct. This option is consistent with the governing fact or the valid combination identified in the question. The option reads: “Neither 1 nor 2” The key Prelims lesson is to test each proposition independently before selecting the combination. Where the question uses words such as 'only', 'all', 'none', 'always' or a precise institutional/geographical association, a single inaccurate component is sufficient to eliminate the option. The answer recorded here follows the official answer key for the question-paper series represented by the uploaded source and has been cross-checked against an independent published key. The explanation is intended for conceptual revision rather than as a reproduction of any third-party solution.