UPSC Prelims 1996 · General Studies
Question 49: Environment and Ecology
Assertion (A): Mangroves are very specialised forest ecosystems of tropical and subtropical regions bordering certain sea coasts. Reason (R): They stabilise the shoreline and act as bulwark against encroachments by sea. In the context of the above two statements, which one of the following is correct?
AnswerThe answer is (a).
A is true: mangroves are specialised, salt-tolerant forests of tropical and subtropical coasts, found along tidal shores, deltas and estuaries. R is also true: their dense roots hold sediment, steady the shoreline and shield the coast from waves and storm surge. The key reads R as explaining A. Remember: mangroves - coastal protection and nursery grounds for fish.
- A. Mangroves are specialised coastal forests of the tropics and subtropics.
- R. Their roots stabilise the shore and protect the coast from the sea.
How you could have got this
This follows an unofficial answer: UPSC has not published its key for this year, and if that answer is wrong, so is this path.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Right per the key: both are true and R is read as explaining A.
- (b) Both are true but R merely describes a function; it is not why the ecosystem is specialised. A fair reading, though the key differs.
- (c) R is true, so 'R is false' cannot hold.
- (d) A is true, so 'A is false' cannot hold.
Worth knowing: R names what mangroves do for the coast, not why they are a specialised ecosystem, so (b) is arguable.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 1996, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.