UPSC Prelims 2015— Question 14

Correct answer: Option B. The equatorial counter-current is an eastward-flowing ocean current between the westward North and South Equatorial Currents. Its development is linked to the accumulation and convergence of water and pressure gradients near the equatorial region. The convergence of the two equatorial currents is therefore the relevant explanation among the options. Option-wise analysis: Option A: “The Earth’s rotation on its axis” is incorrect. It does not match the specific fact, definition, institutional role, geographical association, or constitutional/economic principle required here. The key distinction is the one identified in the core explanation, so this option can be eliminated. Option B: “Convergence of the two equatorial currents” is correct. It directly matches the factual or conceptual requirement tested by the question and is supported by the principle explained above. Option C: “Difference in salinity of water” is incorrect. It does not match the specific fact, definition, institutional role, geographical association, or constitutional/economic principle required here. The key distinction is the one identified in the core explanation, so this option can be eliminated. Option D: “Occurrence of the belt of calm near the equator” is incorrect. It does not match the specific fact, definition, institutional role, geographical association, or constitutional/economic principle required here. The key distinction is the one identified in the core explanation, so this option can be eliminated. Prelims takeaway: Focus on the precise institutional role, constitutional provision, geographical association, or technical definition being tested. UPSC questions often place a broadly familiar fact beside a narrowly incorrect qualifier; identifying that qualifier is essential for elimination.