Difficulty: Easy
Correct Answer: Swan
Explanation:
Given data
Concept/ApproachGroup by typical habitat and lifestyle.
Step-by-step reasoningSparrow, Parrot, and Koel are primarily perching/arboreal birds (tree-dwelling; not waterfowl).Swan is a large aquatic bird (waterfowl) adapted for swimming with webbed feet.
Common pitfallsDo not confuse vocal ability (e.g., parrot talking, koel calling) with habitat; the key separator here is aquatic versus perching birds.
Final AnswerSwan
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