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GS Paper IUPSC Prelims 2000
Biodiversity & Conservation
Question No. 22Interactive Test Mode
00:00
+2-0.66

Q22. Within biological communities, some species are important in determining the ability of a large number of other species to persist in the community. Such species are called:

Within biological communities, some species are important in determining the ability of a large number of other species to persist in the community. Such species are called:

Select the correct option below (or cross out options to eliminate)
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Official Answer Key & Detailed Solution

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Official UPSC Answer KeyUPSC Prelims 2000 • Environment and Ecology

Correct Answer: Option (A) — Keystone species

Concept & Option Breakdown

Standard Reference Verified

Option (a) is correct: A keystone species is one whose impact on its community or ecosystem is disproportionately large relative to its abundance. The removal of a keystone species causes significant ecosystem alterations and can lead to the loss of many other dependent species.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2000 (Q22)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicEnvironment and Ecology → Biodiversity & Conservation
Official Answer KeyOption (A) — Keystone species

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Frequently Asked Questions — UPSC Prelims 2000 Q22

What is the official answer for UPSC Prelims 2000 GS Paper I Question 22 (Environment and Ecology)?

The official UPSC answer key for this 2000 Environment and Ecology (Biodiversity & Conservation) question is Option (A): "Keystone species". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2000 question belong to?

This question belongs to GS Paper I under the subject "Environment and Ecology" and micro-topic "Biodiversity & Conservation". You can explore all repeated questions from Biodiversity & Conservation in Acme AI's 3D Prelims PYQ Realm or practice 50 full-length and sectional tests in the APT Prelims Test Series.

How can I solve this Biodiversity & Conservation UPSC Prelims question using option elimination?

To solve Biodiversity & Conservation questions in UPSC Prelims, identify extreme modifiers, verify core NCERT conceptual definitions, and eliminate mutually contradictory statement pairs before locking your final option.

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