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GS Paper IUPSC Prelims 2021
Biodiversity & Conservation
Question No. 204Interactive Test Mode
00:00
+2-0.66

Q204. Which one of the following is a filter feeder?

Which one of the following is a filter feeder?

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 2021 • Environment and Ecology

Correct Answer: Option (C) — Oyster

Concept & Option Breakdown

Standard Reference Verified

Filter feeders strain suspended matter and food particles directly from water using specialized anatomical sieves or filtering structures. Oysters are bivalve mollusks that pump water through their gills to filter out plankton and organic detritus. Catfish are benthic scavengers/bottom feeders, octopuses are active carnivorous predators, and pelicans are plunge/scoop predators feeding on fish.

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Question Specifications & Syllabus Mapping

Examination & YearUPSC Civil Services Preliminary Examination 2021 (Q204)
Paper & Marking SchemeGS Paper I • 2 Marks (-0.66 Negative for incorrect response)
Syllabus Subject & TopicEnvironment and Ecology → Biodiversity & Conservation
Official Answer KeyOption (C) — Oyster

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Frequently Asked Questions — UPSC Prelims 2021 Q204

What is the official answer for UPSC Prelims 2021 GS Paper I Question 204 (Environment and Ecology)?

The official UPSC answer key for this 2021 Environment and Ecology (Biodiversity & Conservation) question is Option (C): "Oyster". Correct attempts carry 2 Marks with -0.66 Negative penalty for wrong answers.

Which UPSC Prelims syllabus topic does this 2021 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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