UPSC Prelims 2020— Question 98

This question tests low-carbon rural roads. The key concept is: Cold-mix asphalt technology, geotextiles and suitable industrial by-products such as copper slag can reduce energy use, resource demand or waste in road construction. Hot-mix asphalt and Portland cement generally involve higher energy or carbon intensity. Thus the environmentally preferred combination is 1, 2 and 3. The verified answer for the uploaded Set-B paper is option A. Option A — 1, 2 and 3 only: This is the correct option. It matches the verified conclusion because Cold-mix asphalt technology, geotextiles and suitable industrial by-products such as copper slag can reduce energy use, resource demand or waste in road construction. Hot-mix asphalt and Portland cement generally involve higher energy or carbon intensity. Thus the environmentally preferred combination is 1, 2 and 3. The wording of the option is consistent with the governing concept tested by the question. Option B — 2, 3 and 4 only: This is not the correct option. The option does not match the verified combination or conclusion. The decisive point is the distinction explained above: Cold-mix asphalt technology, geotextiles and suitable industrial by-products such as copper slag can reduce energy use, resource demand or waste in road construction. Hot-mix asphalt and Portland cement generally involve higher energy or carbon intensity. Thus the environmentally preferred combination is 1, 2 and 3. Therefore this alternative should be eliminated even if part of its wording appears plausible in isolation. Option C — 4 and 5 only: This is not the correct option. The option does not match the verified combination or conclusion. The decisive point is the distinction explained above: Cold-mix asphalt technology, geotextiles and suitable industrial by-products such as copper slag can reduce energy use, resource demand or waste in road construction. Hot-mix asphalt and Portland cement generally involve higher energy or carbon intensity. Thus the environmentally preferred combination is 1, 2 and 3. Therefore this alternative should be eliminated even if part of its wording appears plausible in isolation. Option D — 1 and 5 only: This is not the correct option. The option does not match the verified combination or conclusion. The decisive point is the distinction explained above: Cold-mix asphalt technology, geotextiles and suitable industrial by-products such as copper slag can reduce energy use, resource demand or waste in road construction. Hot-mix asphalt and Portland cement generally involve higher energy or carbon intensity. Thus the environmentally preferred combination is 1, 2 and 3. Therefore this alternative should be eliminated even if part of its wording appears plausible in isolation. For UPSC-style elimination, first identify the exact proposition being tested, then evaluate each statement independently before comparing the answer codes. Avoid treating a broad or absolute statement as correct merely because its general theme is familiar. The precise qualifiers in the question—such as 'all', 'only', 'cannot', 'largest', 'always' or a specific institutional role—often determine the answer. On that basis, option A is the verified answer.