UPSC Prelims 2007 Q83: Geography – World Physical Geography
Which one among the following rivers is the longest?
- (a) Amazon
- (b) Amur
- (c) Congo
- (d) Lena
Answer: (a) Amazon
Explanation
Longest river among the options — Amazon
| River | Length (approx.) | Continent |
|---|---|---|
| Amazon | ~6,400 km | South America |
| Congo | ~4,700 km | Africa |
| Amur | ~2,800 km (≈ 4,400 km with the Argun headstream) | Asia (Russia-China border) |
| Lena | ~4,400 km | Asia (Siberia) |
The Amazon is the largest river by water volume in the world.
It is either the first or second longest (Nile ~6,650 km is the usual "longest").
None of the other options comes close.
Answer: (a) Amazon.
Why each option is right or wrong
- (a) CORRECT. Amazon (~6,400 km) is far longer than the Congo, Amur and Lena.
- (b) Incorrect. The Amur is about 2,800 km on its own.
- (c) Incorrect. The Congo is about 4,700 km — Africa's second-longest river.
- (d) Incorrect. The Lena is about 4,400 km.
Key point
Amazon ≈ 6,400 km — largest river by discharge; Nile ≈ 6,650 km is usually listed as longest.
Remember
The Amazon is the largest river by volume and among the two longest.
Common mistakes
- Over-thinking the Nile-Amazon debate when the Nile is not even an option.
- Mixing up length and discharge — the Amazon wins on discharge by a huge margin.
- Thinking the Congo is longer because it is the deepest river.
Exam tip
Superlatives: Longest = Nile; Largest volume = Amazon; Deepest = Congo.
Sources
- NCERT Class VIII — Resources and Development (world rivers)
- Encyclopaedia Britannica — Amazon River
- Oxford School Atlas