Answer:
The correct answer is - robin is a bird.
Explanation:
Robin in our mental image, is the closest to a bird, being the most ‘birdiest bird’, that resembles closely a bird prototype - the idea of a bird that have formed in the human perception.
All four named birds have a pair of legs and a pair of wings, meanwhile robin looks more like a classic bird. Goose would be the next one in line, but because of it’s flattened peak and thumpy legs, it is not 100% bird in our image.