UPSC Prelims 2014— Question 60

Correct answer: Option B. Guar gum, obtained from guar seeds, has major industrial uses because of its thickening and gelling properties. It became especially significant in the petroleum industry as a component used in hydraulic fracturing fluids for shale-gas extraction. The question therefore points to guar-seed gum and shale gas. 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: “The oil extracted from seeds is used in the manufacture of biodegradable plastics” Option B: Correct. This option is consistent with the governing fact or the valid combination identified in the question. The option reads: “The gum made from its seeds is used in the extraction of shale gas” 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: “The leaf extract of this plant has the properties of anti-histamines” Option D: 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: “It is a source of high quality biodiesel” 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.