Crocodile
The birds, having evolved from dinosaurs, are their closest living relatives. Crocodilians are the second closest relative of dinosaurs.
No. Whales are not relatives of dinosaurs; they are mammals. The largest living relative of dinosaurs would be the saltwater crocodile.
The closes living relatives to all dinosaurs large and small are birds.
Birds are the closest living relative of a branch of dinosaurs (they're actually descended from dinosaurs whereas we're descended from reptiles), so they would be the most similar.
A Chicken
Birds are the closest living relatives of spinosaurus and all past dinosaurs.
tortoise
The Great Kudu.
Dinosaurs became extinct from starvation, they did not evolve into any other species who's descendants live today. The closest thing you can get to naming an animal who were contemporary with dinosaurs are sharks, and alligators.
It is Alligator.
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crocidiles